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  • 1.
    Sharma, Sumit
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Frodlund, Jonas
    Vastervik Hosp, Sweden.
    Hinkula, Jorma
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Ledin, Torbjörn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Speech language pathology, Audiology and Otorhinolaryngology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Otorhinolaryngology in Linköping.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Detection of rotavirus- and norovirus-specific IgG memory B cells in tonsils2019In: Journal of Medical Virology, ISSN 0146-6615, E-ISSN 1096-9071, Vol. 91, no 2, p. 326-329Article in journal (Refereed)
    Abstract [en]

    Because rotavirus (RV) and norovirus (NoV) are transmitted through the fecal-oral route, tonsils due to their location within the oropharynx may sample or become infected with these viruses. We investigated if RV and NoV RNA/antigen, or virus-specific memory/plasma B cells can be detected in the tonsils. While neither RV/NoV antigen, nor genomic RNA was detected, 90% (27/30) of tonsils tested had RV- and NoV-specific IgG memory B cells. However, the mechanism explaining how these cells get there (whether because of local induction or homing after induction at other sites) and the role these cells might play during active infection is not yet clear.

  • 2.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Genetic Susceptibility to Human Norovirus Infection: An Update2019In: Viruses, ISSN 1999-4915, E-ISSN 1999-4915, Vol. 11, no 3, article id 226Article, review/survey (Refereed)
    Abstract [en]

    Noroviruses are the most common etiological agent of acute gastroenteritis worldwide. Despite their high infectivity, a subpopulation of individuals is resistant to infection and disease. This susceptibility is norovirus genotype-dependent and is largely mediated by the presence or absence of human histo-blood group antigens (HBGAs) on gut epithelial surfaces. The synthesis of these HBGAs is mediated by fucosyl- and glycosyltransferases under the genetic control of the FUT2 (secretor), FUT3 (Lewis) and ABO(H) genes. The so-called non-secretors, having an inactivated FUT2 enzyme, do not express blood group antigens and are resistant to several norovirus genotypes, including the predominant GII.4. Significant genotypic and phenotypic diversity of HBGA expression exists between different human populations. Here, we review previous in vivo studies on genetic susceptibility to norovirus infection. These are discussed in relation to population susceptibility, vaccines, norovirus epidemiology and the impact on public health.

  • 3.
    Bucardo, Filemon
    et al.
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Reyes, Yaoska
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Rönnelid, Ylva
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Gonzalez, Fredman
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Histo-blood group antigens and rotavirus vaccine shedding in Nicaraguan infants2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 10764Article in journal (Refereed)
    Abstract [en]

    ABO, Lewis and secretor histo-blood group antigens (HBGA) are susceptibility factors for rotavirus in a P-genotype dependent manner and can influence IgA seroconversion rates following rotavirus vaccination. To investigate the association between HBGA phenotypes and rotavirus vaccine shedding fecal samples (n = 304) from a total of 141 infants vaccinated with Rotarix (n = 71) and RotaTeq (n = 70) were prospectively sampled in three time frames (= 3, 4-7 and = 8 days) after first vaccination dose. Rotavirus was detected with qPCR and genotypes determined by G/P multiplex PCR and/or sequencing. HBGAs were determined by hemagglutination and saliva based ELISA. Low shedding rates were observed, with slightly more children vaccinated with RotaTeq (19%) than Rotarix (11%) shedding rotavirus at = 4 days post vaccination (DPV). At = 4 DPV no infant of Lewis A (n = 6) or nonsecretor (n = 9) phenotype in the Rotarix cohort shed rotavirus; the same observation was made for Lewis A infants (n = 7) in the RotaTeq cohort. Putative in-vivo gene reassortment among RotaTeq strains occurred, yielding mainly G1P[8] strains. The bovine derived P[5] genotype included in RotaTeq was able to replicate and be shed at long time frames (amp;gt;13 DPV). The results of this study are consistent with that HBGA phenotype influences vaccine strain shedding as similarly observed for natural infections. Due to the low overall shedding rates observed, additional studies are however warranted.

  • 4.
    Piedade, Joao
    et al.
    Univ Nova Lisboa, Portugal.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Esteves, Filipa
    Univ Nova Lisboa, Portugal.
    Esteves, Aida
    Univ Nova Lisboa, Portugal.
    Teodosio, Rosa
    Univ Nova, Portugal.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Hematopoiesis and Developmental Biology. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Istrate, Claudia
    Univ Nova Lisboa, Portugal.
    Molecular epidemiology and host genetics of norovirus and rotavirus infections in Portuguese elderly living in aged care homes2019In: Journal of Medical Virology, ISSN 0146-6615, E-ISSN 1096-9071, Vol. 91, no 6, p. 1014-1021Article in journal (Refereed)
    Abstract [en]

    Norovirus (NoV) and rotavirus group A (RVA) are major agents of acute gastroenteritis worldwide. This study aimed to investigate their epidemiological profile in Portuguese elderly living in long-term care facilities and to assess the host genetic factors mediating infection susceptibility. From November 2013 to June 2015, 636 faecal specimens from 169 elderly, mainly asymptomatic, living in nursing homes in Greater Lisbon and Faro district, Portugal, were collected. NoV and RVA were detected by real-time polymerase chain reaction and NoV genotyped by phylogenetic analysis. NoV detection rate was 7.1% (12 of 169). Three GI.3 and one GII.6 strains were genotyped. RVA detection rate was 3.6% (6 of 169), exclusively in asymptomatic individuals. Host genetic factors associated with infection susceptibility were described on 250 samples by saliva-based enzyme-linked immunosorbent assays. The Lewis-negative phenotype was 8.8% (22 of 250) and the rate of nonsecretors was 16.8% (42 of 250). Association to NoV and RVA infection was performed in the subgroup of individuals (n = 147) who delivered both faecal and saliva samples. The majority of NoV- and RVA-positive individuals (90.9% and 83.3%, respectively) were secretor-positive, with Lewis B phenotype. In a subset of individuals, FUT2 and FUT3 genes were genotyped to assess mutations and validate the secretor and Lewis phenotypes. All sequenced nonsecretors were homozygous for FUT2 nonsense mutation G428A. In this study, low detection rates of NoV and RVA infections were found during two winter seasons. However, even in the absence of any outbreak, the importance of finding these infections in a nonepidemic situation in long-term care facilities may have important implications for infection control.

  • 5.
    Baroni de Moraes, Marcia Terezinha
    et al.
    Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Olivares Olivares, Alberto Ignacio
    Univ Fed Roraima, Brazil; Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Fialho, Alexandre Madi
    Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Malta, Fabio Correia
    Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    da Silva e Mouta Junior, Sergio
    Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Bispo, Romanul de Souza
    Univ Fed Roraima, Brazil.
    Velloso, Alvaro Jorge
    Oswaldo Cruz Fdn FIOCRUZ, Brazil; Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Alves Leitao, Gabriel Azevedo
    Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Cantelli, Carina Pacheco
    Oswaldo Cruz Fdn FIOCRUZ, Brazil; Oswaldo Cruz Fdn FIOCRUZ, Brazil; Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Miagostovich, Marize Pereira
    Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Gagliardi Leite, Jose Paulo
    Oswaldo Cruz Fdn FIOCRUZ, Brazil.
    Phenotyping of Lewis and secretor HBGA from saliva and detection of new FUT2 gene SNPs from young children from the Amazon presenting acute gastroenteritis and respiratory infection2019In: Infection, Genetics and Evolution, ISSN 1567-1348, E-ISSN 1567-7257, Vol. 70, p. 61-66Article in journal (Refereed)
    Abstract [en]

    The Histo-blood group antigens (HBGA) are host genetic factors associated with susceptibility to rotavirus (RV) and human norovirus (HuNoV), the major etiological agents of viral acute gastroenteritis (AGE) worldwide. The FUT2 gene expressing the alpha-1, 2-L- fucosyltransferase enzyme is important for gut HBGA expression, and also provides a composition of the phenotypic profile achieved through mutations occurring in populations with different evolutionary histories; as such, it can be considered a genetic population marker. In this study, Lewis and secretor HBGA phenotyping was performed using 352 saliva samples collected from children between three months and five years old born in the Amazon (Brazil, Venezuela and English Guyana) presenting AGE or acute respiratory infection (ARI), the latter considered as control samples. The total of children phenotyped as secretors was 323, corresponding to 91.80%. From these, 207 (58.80%) had a Le (a + b +) profile. The HBGA profiles were equally found in children with AGE as well as with ARI. The rs1047781 of the FUT2 gene was not detected in DNA from saliva cells with a Le (a + b +) profile. However, mutations not yet described in the FUT2 gene were observed: missense 325A amp;gt; T, 501C amp;gt; T, 585C amp;gt; T, 855A amp;gt; T and missense substitutions 327C amp;gt; T [S (Ser) amp;gt; C (Cys)], 446 T amp;gt; C [L(Leu) amp;gt; P(Pro)], 723C amp;gt; A [N(Asn) amp;gt; K(Lys)], 724A amp;gt; T [I(Ile) amp;gt; F(Phe)], 736C amp;gt; A [H(His) amp;gt; N(Asn)]. The SNP distribution in the FUT2 gene of the analyzed samples was very similar to that described in Asian populations, including indigenous tribes.

  • 6.
    Barbe, Laure
    et al.
    Univ Nantes, France.
    Le Moullac-Vaidye, Beatrice
    Univ Nantes, France.
    Echasserieau, Klara
    Univ Nantes, France; Univ Nantes, France.
    Bernardeau, Karine
    Univ Nantes, France; Univ Nantes, France.
    Carton, Thomas
    Biofortis, France.
    Bovin, Nicolai
    RAS, Russia.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Ruvoen-Clouet, Nathalie
    Univ Nantes, France; Oniris, France.
    Le Pendu, Jacques
    Univ Nantes, France.
    Histo-blood group antigen-binding specificities of human rotaviruses are associated with gastroenteritis but not with in vitro infection2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 12961Article in journal (Refereed)
    Abstract [en]

    Human strains of rotavirus A (RVAs) recognize fucosylated glycans belonging to histo-blood group antigens (HBGAs) through their spike protein VP8*. Lack of these ligands due to genetic polymorphisms is associated with resistance to gastroenteritis caused by P[8] genotype RVAs. With the aim to delineate the contribution of HBGAs in the process, we analyzed the glycan specificity of VP8* proteins from various P genotypes. Binding to saliva of VP8* from P[8] and P[4] genotypes required expression of both FUT2 and FUT3 enzymes, whilst binding of VP8* from the P[14] genotype required FUT2 and A enzymes. We further defined a glycan motif, GlcNAc beta 3Gal beta 4GlcNAc, recognized by P[6] clinical strains. Conversion into Lewis antigens by the FUT3 enzyme impaired recognition, explaining their lower binding to saliva of Lewis positive phenotype. In addition, the presence of neutralizing antibodies was associated with the presence of the FUT2 wild type allele in sera from young healthy adults. Nonetheless, in vitro infection of transformed cell lines was independent of HBGAs expression, indicating that HBGAs are not human RV receptors. The match between results from saliva-based binding assays and the epidemiological data indicates that the polymorphism of human HBGAs controls susceptibility to RVAs, although the exact mechanism remains unclear.

  • 7.
    Devito, Claudia
    et al.
    Swedish Inst Infect Dis Control, Sweden; HD Dept Clin Virol, Sweden.
    Ellegård, Rada
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Clinical genetics.
    Falkeborn, Tina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Microbiology.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Ohlin, Mats
    Lund Univ, Sweden.
    Larsson, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Broliden, Kristina
    Karolinska Inst, Sweden.
    Hinkula, Jorma
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Human IgM monoclonal antibodies block HIV-transmission to immune cells in cervico-vaginal tissues and across polarized epithelial cells in vitro2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 10180Article in journal (Refereed)
    Abstract [en]

    The importance of natural IgM antibodies in protection against infections is still emerging and these antibodies have a potential role in the maintenance of homeostasis through clearance of apoptotic bodies, complement-dependent mechanisms, inflammation and exclusion of misfolded proteins. Natural IgM act as a first line of defence against unknown hazardous factors and are present in most vertebrates. We investigated the functional capacity of anti-HIV-1 IgM monoclonal antibodies, from a combinatorial Fab library derived from healthy individuals, and evaluated their protective role in inhibiting HIV-1 in vitro when passing across the human mucosal epithelial barrier. Primary HIV-1 isolates were efficiently transmitted over the tight polarized epithelial cells when added to their apical surface. Efficient inhibition of HIV-1 transmission was achieved when anti-HIV-1 IgM monoclonal antibodies were added to the basolateral side of the cells. Two of these human IgM MoAbs had the ability to neutralize HIV and reduced infection of dendritic cells in primary cervico-vaginal tissue biopsies in vitro. This indicates a potential role of natural IgM antibodies in the reduction of HIV-1 transmission in mucosal tissues and improve our understanding of how natural IgM antibodies against a neutralizing epitope could interfere with viral transmission.

  • 8.
    Westerberg, Sonja
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Rajan, Anandi
    Umea Univ, Sweden.
    Loitto, Vesa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Persson, B. David
    Umea Univ, Sweden.
    Allard, Annika
    Umea Univ, Sweden.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Magnusson, Karl-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Arnberg, Niklas
    Umea Univ, Sweden.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Interaction of Human Enterochromaffin Cells with Human Enteric Adenovirus 41 Leads to Serotonin Release and Subsequent Activation of Enteric Glia Cells2018In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 92, no 7, article id e00026-18Article in journal (Refereed)
    Abstract [en]

    Human adenovirus 41 (HAdV-41) causes acute gastroenteritis in young children. The main characteristics of HAdV-41 infection are diarrhea and vomiting. Nevertheless, the precise mechanism of HAdV-41-induced diarrhea is unknown, as a suitable small-animal model has not been described. In this study, we used the human midgut carcinoid cell line GOT1 to investigate the effect of HAdV-41 infection and the individual HAdV-41 capsid proteins on serotonin release by enterochromaffin cells and on enteric glia cell (EGC) activation. We first determined that HAdV-41 could infect the enterochromaffin cells. Immunofluorescence staining revealed that the cells expressed HAdV-41-specific coxsackievirus and adenovirus receptor (CAR); flow cytometry analysis supported these findings. HAdV-41 infection of the enterochromaffin cells induced serotonin secretion dose dependently. In contrast, control infection with HAdV-5 did not induce serotonin secretion in the cells. Confocal microscopy studies of enterochromaffin cells infected with HAdV-41 revealed decreased serotonin immunofluorescence compared to that in uninfected cells. Incubation of the enterochromaffin cells with purified HAdV-41 short fiber knob and hexon proteins increased the serotonin levels in the harvested cell supernatant significantly. HAdV-41 infection could also activate EGCs, as shown in the significantly altered expression of glia fibrillary acidic protein (GFAP) in EGCs incubated with HAdV-41. The EGCs were also activated by serotonin alone, as shown in the significantly increased GFAP staining intensity. Likewise, EGCs were activated by the cell supernatant of HAdV-41-infected enterochromaffin cells. IMPORTANCE The nonenveloped human adenovirus 41 causes diarrhea, vomiting, dehydration, and low-grade fever mainly in children under 2 years of age. Even though acute gastroenteritis is well described, how human adenovirus 41 causes diarrhea is unknown. In our study, we analyzed the effect of human adenovirus 41 infection on human enterochromaffin cells and found it stimulates serotonin secretion in the cells, which is involved in regulation of intestinal secretion and gut motility and can also activate enteric glia cells, which are found in close proximity to enterochromaffin cells in vivo. This disruption of gut barrier homeostasis as maintained by these cells following human adenovirus 41 infection might be a mechanism in enteric adenovirus pathogenesis in humans and could indicate a possible serotonin-dependent cross talk between human adenovirus 41, enterochromaffin cells, and enteric glia cells.

  • 9.
    Bonkoungou, Isidore Juste O.
    et al.
    Univ Ouaga, Burkina Faso; Natl Publ Hlth Lab, Burkina Faso.
    Ouedraogo, Nafissatou
    Univ Ouaga, Burkina Faso.
    Tamini, Laure
    Univ Ouaga, Burkina Faso; Charles de Gaulle Pediat Univ Hosp, Burkina Faso.
    Teguera, Rabieta Kouboura
    Natl Publ Hlth Lab, Burkina Faso.
    Yameogo, Pouire
    Natl Publ Hlth Lab, Burkina Faso.
    Drabo, Maxime Koine
    Natl Publ Hlth Lab, Burkina Faso.
    Medah, Isaie
    Minist Hlth, Burkina Faso.
    Barro, Nicolas
    Univ Ouaga, Burkina Faso.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Rotavirus and norovirus in children with severe diarrhea in Burkina Faso before rotavirus vaccine introduction2018In: Journal of Medical Virology, ISSN 0146-6615, E-ISSN 1096-9071, Vol. 90, no 9, p. 1453-1460Article in journal (Refereed)
    Abstract [en]

    Burkina Faso introduced rotavirus vaccine (RotaTeq) to the national immunization program in November 2013. This study describes the detection rates, clinical profiles, and molecular epidemiology of rotavirus and norovirus (NoV) infections among children amp;lt;5 years hospitalized (n=154) because of acute diarrhea in Ouagadougou, Burkina Faso, from December 2012 to November 2013, just before the start of vaccination. Overall, 44% and 23% of fecal samples were positive for rotavirus and NoV, respectively, most of them detected during the cold dry season (December-March). The predominant G/P combinations were G12P[8] (47%) and G6P[6] (30%). G2P[4] (n=3), G12P[6] (n=3), and G6P[8] (n=1) werealso detected. Nearly all (94%) successfully genotyped NoV strains belonged to genotype GII.4. The predominance of rotavirus and NoV was noteworthy in the age group 6 months, with 67% rotavirus and 22% NoV, respectively. Vomiting was significantly more common among rotavirus-infected children. To conclude, this study shows high detection rates of both rotavirus and NoV in children with severe diarrhea in Burkina Faso just before the introduction of rotavirus group A vaccination. The results can be used for estimating the impact of rotavirus group A vaccination, which started in the end of 2013. Furthermore, this study shows that the G6P[6] rotavirus strains emerging in Burkina Faso in 2010 is now established as a regionally important genotype.

  • 10.
    Bucardo, Filemon
    et al.
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Reyes, Yaoska
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Gonzalez, Fredman
    Natl Autonomous Univ Nicaragua, Nicaragua.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    The Lewis A phenotype is a restriction factor for Rotateq and Rotarix vaccine-take in Nicaraguan children2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 1502Article in journal (Refereed)
    Abstract [en]

    Histo-blood group antigens (HBGAs) and the Lewis and secretor antigens are associated with susceptibility to rotavirus infection in a genotype-dependent manner. Nicaraguan children were prospectively enrolled in two cohorts vaccinated with either RotaTeq RV5 (n = 68) or Rotarix RV1 (n = 168). Lewis and secretor antigens were determined by saliva phenotyping and genotyping. Seroconversion was defined as a 4-fold increase in plasma IgA antibody titer 1 month after administration of the first dose of the vaccine. Regardless of the vaccine administered, significantly fewer of the children with Lewis A phenotype (0/14) seroconverted after receiving the first vaccine dose compared to 26% (45/175) of those with the Lewis B phenotype and 32% (15/47) of the Lewis negative individuals (P amp;lt; 0.01). Furthermore, following administration of the RV1 vaccine, secretor-positive ABO blood group B children seroconverted to a significantly lesser extent (5%) compared to secretor-positive children with ABO blood groups A (26%) and O (27%) (P amp;lt; 0.05). Other factors such as pre-vaccination titers, sex, breastfeeding, and calprotectin levels did not influence vaccine-take. Differences in HBGA expression appear to be a contributing factor in the discrepancy in vaccine-take and thus, in vaccine efficacy in different ethnic populations.

  • 11.
    Sharma, Sumit
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Carlsson, Beatrice
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Czako, Rita
    Baylor Coll Med, TX 77030 USA; Baylor Coll Med, TX 77030 USA.
    Vene, Sirkka
    Public Health Agency Sweden, Sweden.
    Haglund, Mats
    County Hospital Kalmar, Sweden.
    Ludvigsson, Johnny
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping.
    Larson, Goran
    University of Gothenburg, Sweden.
    Hammarstrom, Lennart
    Karolinska Institute, Sweden.
    Sosnovtsev, Stanislav V.
    NIAID, MD 20892 USA.
    Atmar, Robert L.
    Baylor Coll Med, TX 77030 USA; Baylor Coll Med, TX 77030 USA.
    Green, Kim Y.
    NIAID, MD 20892 USA.
    Estes, Mary K.
    Baylor Coll Med, TX 77030 USA; Baylor Coll Med, TX 77030 USA.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Institute, Sweden.
    Human Sera Collected between 1979 and 2010 Possess Blocking-Antibody Titers to Pandemic GII.4 Noroviruses Isolated over Three Decades2017In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 91, no 14, article id UNSP e00567Article in journal (Refereed)
    Abstract [en]

    The emergence of pandemic GII.4 norovirus (NoV) strains has been proposed to occur due to changes in receptor usage and thereby to lead to immune evasion. To address this hypothesis, we measured the ability of human sera collected between 1979 and 2010 to block glycan binding of four pandemic GII. 4 noroviruses isolated in the last 4 decades. In total, 268 sera were investigated for 50% blocking titer (BT50) values of virus-like particles (VLPs) against pig gastric mucin (PGM) using 4 VLPs that represent different GII. 4 norovirus variants identified between 1987 and 2012. Pre- and postpandemic sera (sera collected before and after isolation of the reference NoV strain) efficiently prevented binding of VLP strains MD145 (1987), Grimsby (1995), and Houston (2002), but not the Sydney (2012) strain, to PGM. No statistically significant difference in virus-blocking titers was observed between pre- and postpandemic sera. Moreover, paired sera showed that blocking titers of amp;gt;= 160 were maintained over a 6-year period against MD145, Grimsby, and Houston VLPs. Significantly higher serum blocking titers (geometric mean titer [GMT], 1,704) were found among IgA-deficient individuals than among healthy blood donors (GMT, 90.9) (P amp;lt; 0.0001). The observation that prepandemic sera possess robust blocking capacity for viruses identified decades later suggests a common attachment factor, at least until 2002. Our results indicate that serum IgG possesses antibody-blocking capacity and that blocking titers can be maintained for at least 6 years against 3 decades of pandemic GII. 4 NoV. IMPORTANCE Human noroviruses (NoVs) are the major cause of acute gastroenteritis worldwide. Histo-blood group antigens (HBGAs) in saliva and gut recognize NoV and are the proposed ligands that facilitate infection. Polymorphisms in HBGA genes, and in particular a nonsense mutation in FUT2 (G428A), result in resistance to global dominating GII. 4 NoV. The emergence of new pandemic GII. 4 strains occurs at intervals of several years and is proposed to be attributable to epochal evolution, including amino acid changes and immune evasion. However, it remains unclear whether exposure to a previous pandemic strain stimulates immunity to a pandemic strain identified decades later. We found that prepandemic sera possess robust virus-blocking capacity against viruses identified several decades later. We also show that serum lacking IgA antibodies is sufficient to block NoV VLP binding to HBGAs. This is essential, considering that 1 in every 600 Caucasian children is IgA deficient.

  • 12.
    Hagbom, Marie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Novak, Daniel
    Sahlgrens University Hospital, Sweden.
    Ekstrom, Malin
    Sahlgrens University Hospital, Sweden.
    Khalid, Younis
    Sahlgrens University Hospital, Sweden.
    Andersson, Maria
    University of Gothenburg, Sweden.
    Lindh, Magnus
    University of Gothenburg, Sweden.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Institute, Sweden.
    Ondansetron treatment reduces rotavirus symptoms-A randomized double-blinded placebo-controlled trial2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 10, article id e0186824Article in journal (Refereed)
    Abstract [en]

    Background Rotavirus and norovirus cause acute gastroenteritis with severe diarrhoea and vomiting, symptoms that may lead to severe dehydration and death. The objective of this randomized double-blinded placebo-controlled study was to investigate whether ondansetron, a serotonin receptor antagonist could attenuate rotavirus-and norovirus-induced vomiting and diarrhoea, which would facilitate oral rehydration and possibly accelerate recovery and reduce need for hospitalization. Methods Children with acute gastroenteritis, aged 6 months to 16 years where enrolled (n = 104) and randomized to one single oral dose (0.15mg/kg) of ondansetron (n = 52) or placebo (n = 52). The number of diarrhoea and vomiting episodes during the 24 hours following treatment was reported as well as the number of days with symptoms. Pathogens in faeces were diagnosed by real-time PCR. Outcome parameters were analyzed for rotavirus-and noroviruspositive children. Results One dose of oral ondansetron reduced duration of rotavirus clinical symptoms (p = 0.014), with a median of two days. Furthermore, ondansetron reduced diarrhea episodes, most pronounced in children that had been sick for more than 3 days before treatment (p = 0.028). Conclusion Ondansetron may be a beneficial treatment for children with rotavirus gastroenteritis.

  • 13.
    Bucardo, Filemon
    et al.
    National Autonomous University of Nicaragua, Nicaragua.
    Reyes, Yaoska
    National Autonomous University of Nicaragua, Nicaragua.
    Becker-Dreps, Sylvia
    University of N Carolina, NC USA.
    Bowman, Natalie
    University of N Carolina, NC USA.
    Gruber, Joann F.
    University of N Carolina, NC USA.
    Vinje, Jan
    National Centre Immunizat and Resp Disease, GA USA.
    Espinoza, Felix
    National Autonomous University of Nicaragua, Nicaragua.
    Paniagua, Margarita
    National Autonomous University of Nicaragua, Nicaragua.
    Balmaseda, Angel
    Minist Heatlh, Nicaragua.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Pediatric norovirus GII.4 infections in Nicaragua, 1999-20152017In: Infection, Genetics and Evolution, ISSN 1567-1348, E-ISSN 1567-7257, Vol. 55, p. 305-312Article in journal (Refereed)
    Abstract [en]

    Objectives: Investigate clinical and epidemiological factors of pediatric GII.4 norovirus infections in children with acute gastroenteritis (AGE) in Nicaragua between 1999 and 2015. Methods: We retrospectively analyzed laboratory and epidemiologic data from 1,790 children amp;lt;= 7 years with AGE from 6 hospitals in Nicaragua (n = 538), and 3 community clinics (n = 919) and households (n = 333) in Leon, between 1999 and 2015. Moreover, asymptomatic children from community clinics (n = 162) and households (n = 105) were enrolled. Norovirus was detected by real-time PCR and genotyped by sequencing the N-terminal and shell region of the capsid gene. Results: Norovirus was found in 19% (n = 338) and 12% (n = 32) of children with and without AGE, respectively. In total, 20 genotypes including a tentatively new genotype were detected. Among children with AGE, the most common genotypes were GII.4 (53%), GII.14 (7%), GII.3 (6%) and GI.3 (6%). In contrast, only one (1.4%) GII.4 was found in asymptomatic children. The prevalence of GII.4 infections was significantly higher in children between 7 and 12 months of age. The prevalence of GII.4 was lowest in households (38%), followed by community clinics (50%) and hospitals (75%). Several different GII.4 variants were detected and their emergence followed the global temporal trend. Conclusions: Overall our study found the predominance of pediatric GII.4 norovirus infections in Nicaragua mostly occurring in children between 7 and 12 months of age, implicating GII.4 as the main norovirus vaccine target.

  • 14.
    Crawford, Sue E.
    et al.
    Baylor Coll Med, TX 77030 USA.
    Ramani, Sasirekha
    Baylor Coll Med, TX 77030 USA.
    Tate, Jacqueline E.
    US Centre Disease Control and Prevent, GA USA.
    Parashar, Umesh D.
    US Centre Disease Control and Prevent, GA USA.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Institute, Sweden.
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Franco, Manuel A.
    Pontificia University of Javeriana, Colombia.
    Greenberg, Harry B.
    Stanford University, CA 94305 USA.
    ORyan, Miguel
    University of Chile, Chile; University of Chile, Chile.
    Kang, Gagandeep
    Translat Health and Science Technology Institute, India; Christian Medical Coll and Hospital, India.
    Desselberger, Ulrich
    University of Cambridge, England.
    Estes, Mary K.
    Baylor Coll Med, TX 77030 USA.
    Rotavirus infection2017In: NATURE REVIEWS DISEASE PRIMERS, ISSN 2056-676X, Vol. 3, article id 17083Article in journal (Refereed)
    Abstract [en]

    Rotavirus infections are a leading cause of severe, dehydrating gastroenteritis in children amp;lt;5 years of age. Despite the global introduction of vaccinations for rotavirus over a decade ago, rotavirus infections still result in amp;gt;200,000 deaths annually, mostly in low-income countries. Rotavirus primarily infects enterocytes and induces diarrhoea through the destruction of absorptive enterocytes (leading to malabsorption), intestinal secretion stimulated by rotavirus non-structural protein 4 and activation of the enteric nervous system. In addition, rotavirus infections can lead to antigenaemia (which is associated with more severe manifestations of acute gastroenteritis) and viraemia, and rotavirus can replicate in systemic sites, although this is limited. Reinfections with rotavirus are common throughout life, although the disease severity is reduced with repeat infections. The immune correlates of protection against rotavirus reinfection and recovery from infection are poorly understood, although rotavirus-specific immunoglobulin A has a role in both aspects. The management of rotavirus infection focuses on the prevention and treatment of dehydration, although the use of antiviral and anti-emetic drugs can be indicated in some cases.

  • 15.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Kambhampati, Anita
    Centre Disease Control and Prevent, USA.
    Lopman, Ben
    Centre Disease Control and Prevent, USA.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Innate Resistance and Susceptibility to Norovirus Infection2016In: PLoS Pathogens, ISSN 1553-7366, E-ISSN 1553-7374, Vol. 12, no 4, p. e1005385-Article in journal (Refereed)
    Abstract [en]

    n/a

  • 16.
    Kang, Gagandeep
    et al.
    Christian Medical Coll and Hospital, India.
    Thuppal, Sowmyanarayanan V.
    Christian Medical Coll and Hospital, India.
    Srinivasan, Rajan
    Christian Medical Coll and Hospital, India.
    Sarkar, Rajiv
    Christian Medical Coll and Hospital, India.
    Subashini, Beula
    Christian Medical Coll and Hospital, India.
    Venugopal, Srinivasan
    Christian Medical Coll and Hospital, India.
    Sindhu, Kulandaipalayam
    Christian Medical Coll and Hospital, India.
    Anbu, Dhivya
    Christian Medical Coll and Hospital, India.
    Parez, Nathalie
    Hop Enfants Armand Trousseau, France.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Bose, Anuradha
    Christian Medical Coll and Hospital, India.
    Racecadotril in the management of rotavirus and non-rotavirus diarrhea in under-five children: Two randomized, double-blind, placebo-controlled trials2016In: Indian Pediatrics, ISSN 0019-6061, E-ISSN 0974-7559, Vol. 53, no 7, p. 595-600Article in journal (Refereed)
    Abstract [en]

    To study the effect of racecadotril on reduction in the duration of acute rotavirus and non-rotavirus diarrhea. Two randomized double-blind placebo-controlled trials Community-based trial in an urban area in Vellore, hospital-based trial at a secondary hospital in Vellore 199 and 130 3-59 month old children in the community- and hospital-based trials, respectively. Racecadotril (1.5 mg/kg/dose, thrice a day for three days) or placebo were given to manage acute diarrhea in both trials. Median duration of diarrhea. Among 124 children completing the hospital trial, the median duration of diarrhea was 25 h in both arms (P=0.5); median total stool weight was 74 g/kg and 53.5 g/kg in racecadotril group and placebo group, respectively (P=0.4); and average fluid intake per day was 3.6 mL/kg/h and 3mL/kg/h in racecadotril and placebo arms, respectively (P=0.3). Among rotavirus-positive children, median duration of diarrhea was 26.9 h and 30.2 h in racecadotril and placebo arms, respectively (P=0.7). In the community, 196 completed the trial, the median duration of diarrhea was 2 days for both arms (P=0.8) and rotavirus positive children had similar outcomes with median diarrheal duration of 3 d in both arms (P=0.4). Treatment with racecadotril did not reduce diarrheal duration, stool volume or the requirement for fluid replacement in children with acute gastroenteritis, both with and without rotavirus infection.

  • 17.
    Bialowas, Sonja
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Karlsson, Thommie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Magnusson, Karl-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Rotavirus and Serotonin Cross-Talk in Diarrhoea2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 7, p. e0159660-Article in journal (Refereed)
    Abstract [en]

    Rotavirus (RV) has been shown to infect and stimulate secretion of serotonin from human enterochromaffin (EC) cells and to infect EC cells in the small intestine of mice. It remains to identify which intracellularly expressed viral protein(s) is responsible for this novel property and to further establish the clinical role of serotonin in RV infection. First, we found that siRNA specifically silencing NSP4 (siRNA(NSP4)) significantly attenuated secretion of serotonin from Rhesus rotavirus (RRV) infected EC tumor cells compared to siRNA(VP4), siRNA(VP6) and siRNA(VP7). Second, intracellular calcium mobilization and diarrhoeal capacity from virulent and avirulent porcine viruses correlated with the capacity to release serotonin from EC tumor cells. Third, following administration of serotonin, all (10/10) infants, but no (0/8) adult mice, responded with diarrhoea. Finally, blocking of serotonin receptors using Ondansetron significantly attenuated murine RV (strain EDIM) diarrhoea in infant mice (2.9 vs 4.5 days). Ondansetron-treated mice (n = 11) had significantly (p amp;lt; 0.05) less diarrhoea, lower diarrhoea severity score and lower total diarrhoea output as compared to mock-treated mice (n = 9). Similarly, Ondansetron-treated mice had better weight gain than mock-treated animals (p amp;lt; 0.05). A most surprising finding was that the serotonin receptor antagonist significantly (p amp;lt; 0.05) also attenuated total viral shedding. In summary, we show that intracellularly expressed NSP4 stimulates release of serotonin from human EC tumor cells and that serotonin participates in RV diarrhoea, which can be attenuated by Ondansetron.

  • 18.
    Hagbom, Marie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nybom, Rolf
    Karolinska Institute, Sweden.
    Hedlund, Kjell-Olof
    Swedish Institute Communicable Disease Control, Sweden.
    Wigzell, Hans
    Karolinska Institute, Sweden.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Ionizing air affects influenza virus infectivity and prevents airborne-transmission2015In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, no 11431Article in journal (Refereed)
    Abstract [en]

    By the use of a modified ionizer device we describe effective prevention of airborne transmitted influenza A (strain Panama 99) virus infection between animals and inactivation of virus (greater than 97%). Active ionizer prevented 100% (4/4) of guinea pigs from infection. Moreover, the device effectively captured airborne transmitted calicivirus, rotavirus and influenza virus, with recovery rates up to 21% after 40 min in a 19 m(3) room. The ionizer generates negative ions, rendering airborne particles/aerosol droplets negatively charged and electrostatically attracts them to a positively charged collector plate. Trapped viruses are then identified by reverse transcription quantitative real-time PCR. The device enables unique possibilities for rapid and simple removal of virus from air and offers possibilities to simultaneously identify and prevent airborne transmission of viruses.

  • 19.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Bucardo, Filemon
    University of Leon, Nicaragua.
    Nasir, Waqas
    University of Gothenburg, Sweden.
    Gunaydin, Gokce
    Karolinska Institute, Sweden.
    Ouermi, Djeneba
    University of Ouagadougou, Burkina Faso.
    Nitiema, Leon W.
    University of Ouagadougou, Burkina Faso.
    Becker-Dreps, Sylvia
    University of N Carolina, NC USA.
    Simpore, Jacques
    University of Ouagadougou, Burkina Faso.
    Hammarstrom, Lennart
    Karolinska Institute, Sweden.
    Larson, Goran
    University of Gothenburg, Sweden.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Both Lewis and Secretor Status Mediate Susceptibility to Rotavirus Infections in a Rotavirus Genotype-Dependent Manner2014In: Clinical Infectious Diseases, ISSN 1058-4838, E-ISSN 1537-6591, Vol. 59, no 11, p. 1567-1573Article in journal (Refereed)
    Abstract [en]

    Background. The live oral rotavirus (RV) vaccines have shown a reduced efficacy in Africa. Recent in vitro studies have shown binding of the RV surface protein (VP4) to histo-blood group antigens (HBGAs) in an RV genotype-dependent manner, suggesting them to be putative receptors for RV. The diversity of HBGA phenotypes in different ethnic populations, combined with prevalence/absence of specific RV genotypes, led us to hypothesize whether the genetic variations in HBGAs in a population limit susceptibility to certain RV genotypes, plausibly leading to reduced vaccine efficacy. Methods. Association between HBGAs status and susceptibility to RV P genotypes was investigated in children in Burkina Faso and Nicaragua. In total, 242 children with diarrhea in Burkina Faso and Nicaragua were investigated, 93 of whom were RV positive. Results. In Burkina Faso, the P[8] RV strains (n = 27) infected only Lewis-and secretor-positive children (27/27; P less than .0001), but no Lewis-negative children. In contrast, the P[6] strains (n = 27) infected predominantly Lewis-negative children (n = 18; P less than.0001) but also Lewis-positive children, irrespective of their secretor status. The results from Nicaragua confirmed that all P[8]-infected children (n = 22) were secretor Lewis positive. Conclusions. As VP4 of genotype P[8] is a component of current RV vaccines, our finding that Lewis-negative children are resistant to P[8] strains provides a plausible explanation for the reduced vaccine efficacy in populations with a high percentage of Lewis-negative individuals, such as in Africa. Furthermore, our findings provide a plausible explanation as to why P[6] RV strains are more common in Africa.

  • 20.
    Becker-Dreps, Sylvia
    et al.
    University of N Carolina, NC 27599 USA.
    Bucardo, Filemon
    National Autonomous University of Nicaragua, Nicaragua.
    Vilchez, Samuel
    National Autonomous University of Nicaragua, Nicaragua.
    Enrique Zambrana, Luis
    Centre Epidemiol and Health CIDS, Nicaragua.
    Liu, Lan
    University of N Carolina, NC USA.
    Weber, David J.
    University of N Carolina, NC 27599 USA.
    Pena, Rodolfo
    Centre Health Research CIS, Nicaragua.
    Barclay, Leslie
    Centre Disease Control and Prevent, GA USA.
    Vinje, Jan
    Centre Disease Control and Prevent, GA USA.
    Hudgens, Michael G.
    University of N Carolina, NC USA.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Morgan, Douglas R.
    University of N Carolina, NC 27599 USA; Vanderbilt University, TN 37235 USA.
    Espinoza, Felix
    National Autonomous University of Nicaragua, Nicaragua.
    Paniagua, Margarita
    National Autonomous University of Nicaragua, Nicaragua.
    Etiology of Childhood Diarrhea After Rotavirus Vaccine Introduction A Prospective, Population-based Study in Nicaragua2014In: The Pediatric Infectious Disease Journal, ISSN 0891-3668, E-ISSN 1532-0987, Vol. 33, no 11, p. 1156-1163Article in journal (Refereed)
    Abstract [en]

    Background: Nicaragua was the first developing nation to implement routine immunization with the pentavalent rotavirus vaccine (RV5). In this RV5-immunized population, understanding infectious etiologies of childhood diarrhea is necessary to direct diarrhea treatment and prevention efforts. Methods: We followed a population-based sample of children less than5 years in Leon, Nicaragua for diarrhea episodes through household visits. Information was obtained on RV5 history and sociodemographics. Stool samples collected during diarrhea episodes and among healthy children underwent laboratory analysis for viral, bacterial and parasitic enteropathogens. Detection frequency and incidence of each enteropathogen was calculated. Results: The 826 children in the cohort experienced 677 diarrhea episodes during 607.5 child-years of exposure time (1.1 episodes per child-year). At least 1 enteropathogen was detected among 61.1% of the 337 diarrheal stools collected. The most common enteropathogens among diarrheal stools were: norovirus (20.4%), sapovirus (16.6%), enteropathogenic Escherichia coli (11.3%), Entamoeba histolytica/dispar (8.3%), Giardia lamblia (8.0%) and enterotoxigenic E. coli (7.7%), with rotavirus detected among 5.3% of diarrheal stools. Enteropathogenic Escherichia coli and enterotoxigenic E. coli were frequently detected among stools from healthy children. Among children with diarrhea, norovirus was more commonly detected among younger children (less than2 years) and G. lamblia was more commonly detected among older children (2-4 years). The mean age of rotavirus detection was 34.6 months. Conclusions: In this Central American community after RV5 introduction, rotavirus was not commonly detected among children with diarrhea. Prevention and appropriate management of norovirus and sapovirus should be considered to further reduce the burden of diarrheal disease.

  • 21.
    Gunaydin, Gokce
    et al.
    Karolinska University Hospital, Sweden .
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Hammarstrom, Lennart
    Karolinska University Hospital, Sweden .
    Mutations in Toll-Like Receptor 3 Are Associated with Elevated Levels of Rotavirus-Specific IgG Antibodies in IgA-Deficient but Not IgA-Sufficient Individuals2014In: Clinical and Vaccine Immunology, ISSN 1556-6811, E-ISSN 1556-679X, Vol. 21, no 3, p. 298-301Article in journal (Refereed)
    Abstract [en]

    Double-stranded RNA (dsRNA) triggers immune-mediated responses through toll-like receptor 3 (TLR3), which is involved in innate antiviral defense. Low expression of TLR3 was recently suggested to contribute to susceptibility to rotavirus infection. Thus, we investigated the role of two TLR3 polymorphisms (rs3775291 and rs5743305), both of which resulted in reduced protein function or expression, in healthy blood donors and IgA-deficient (IgAD) individuals. These polymorphisms were associated with elevated rotavirus-specific IgG titers in IgAD individuals but not in healthy individuals. Thus, we propose that TLR3 signaling does not contribute to the rotavirus-specific antibody response in IgA-sufficient individuals, whereas it is associated with elevated antibody titers in IgAD individuals.

  • 22.
    Nenonen, Nancy P.
    et al.
    University of Gothenburg, Sweden .
    Hannoun, Charles
    University of Gothenburg, Sweden .
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Toren, Kjell
    University of Gothenburg, Sweden .
    Andersson, Lars-Magnus
    University of Gothenburg, Sweden .
    Westin, Johan
    University of Gothenburg, Sweden .
    Bergstrom, Tomas
    University of Gothenburg, Sweden .
    Norovirus GII.4 Detection in Environmental Samples from Patient Rooms during Nosocomial Outbreaks2014In: Journal of Clinical Microbiology, ISSN 0095-1137, E-ISSN 1098-660X, Vol. 52, no 7, p. 2352-2358Article in journal (Refereed)
    Abstract [en]

    Norovirus (NoV) is an important cause of nosocomial gastroenteric outbreaks. This 5-month study was designed to characterize NoV contamination and airborne dispersal in patient rooms during hospital outbreaks. Air vents, overbed tables, washbasins, dust, and virus traps designed to collect charged particles from the air were swabbed to investigate the possibility of NoV contamination in patient rooms during outbreaks in seven wards and in an outbreak-free ward. Symptomatic inpatients were also sampled. Nucleic acid extracts of the samples were examined for NoV RNA using genogroup I (GI) and GII real-time reverse transcription-PCR (RT-PCR). The NoV strains were characterized by RT-PCR, sequencing, and phylogenetic analysis of the RNA-dependent RNA-polymerase-N/S capsid-coding region (1,040 nucleotides [nt]). Patient strains from two outbreaks in one ward were sequenced across the RNA-dependent-RNA-polymerase major capsid-coding region (2.5 kb), including the hypervariable P2 domain. In the outbreak wards, NoV GII was detected in 48 of 101 (47%) environmental swabs and 63 of 108 patients (58%); NoV genotype II.4 was sequenced from 18 environmental samples, dust (n = 8), virus traps (n = 4), surfaces (n = 6), and 56 patients. In contrast, NoV GII was detected in 2 (GII. 4) of 28 (7%) environmental samples and in 2 (GII. 6 and GII. 4) of 17 patients in the outbreak-free ward. Sequence analyses revealed a high degree of similarity (greater than99.5%, 1,040 nt) between NoV GII.4 environmental and patient strains from a given ward at a given time. The strains clustered on 11 subbranches of the phylogenetic tree, with strong correlations to time and place. The high nucleotide similarity between the NoV GII.4 strains from patients and their hospital room environment provided molecular evidence of GII.4 dispersal in the air and dust; therefore, interventional cleaning studies are justified.

  • 23.
    Mickiene, Aukse
    et al.
    Lithuanian University of Health Science, Lithuania; Karolinska University Hospital Huddinge, Sweden.
    Pakalniene, Jolita
    Lithuanian University of Health Science, Lithuania.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Carlsson, Beatrice
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Lindquist, Lars
    Karolinska University Hospital Huddinge, Sweden.
    Polymorphisms in Chemokine Receptor 5 and Toll-Like Receptor 3 Genes Are Risk Factors for Clinical Tick-Borne Encephalitis in the Lithuanian Population2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 9, p. e106798-Article in journal (Refereed)
    Abstract [en]

    Background: Tick-borne encephalitis virus (TBEV) infections can be asymptomatic or cause moderate to severe injuries of the nervous system. We previously reported that a nonfunctional chemokine receptor 5 (CCR5) and a functional Toll-like receptor 3 (TLR3) predispose adults to clinical tick-borne encephalitis (TBE). This study expands our previous findings and further examines polymorphisms in CCR5 and TLR3 genes in different age and disease severity groups. Methods: 117 children and 129 adults, stratified into mild, moderate and severe forms of TBE, and 103 adults with severe TBE were analyzed. 135 healthy individuals and 79 patients with aseptic meningoencephalitis served as controls. CCR5 delta 32 and rs3775291 TLR3 genotypes were established by pyrosequencing, and their frequencies were analyzed using recessive genetic, genotype and allelic models. Findings: The prevalence of CCR5 Delta 32 homozygotes was higher in children (2.5%), in adults with severe TBE (1.9%), and in the combined cohort of TBE patients (2.3%) than in controls (0%) (pless than0.05). The nonfunctional homozygous TLR3 genotype was less prevalent among the combined TBE cohort (11.5%) than among controls (19.9%) (p = 0.025), but did not differ between children TBE and controls. The genotype and allele prevalence of CCR5 and TLR3 did not differ in children nor adult TBE cohorts stratified by disease severity. However, in the severe adult TBE cohort, homozygous functional TLR3 genotype and wt allele were less prevalent compared to the adult cohort with the whole disease severity spectrum (44.4% vs 59.8% p = 0.022 and 65.2% vs 76.4% p = 0.009; respectively). Conclusions: Independently of age, nonfunctional CCR5D32 mutation is a significant risk factor for development of clinical TBE, but not for disease severity. The polymorphism of TLR3 gene predisposes to clinical TBE in adults only and may be associated with disease severity. Further studies are needed to clarify the role of these polymorphisms in susceptibility to TBEV infection.

  • 24.
    Bucardo, Filemon
    et al.
    University of Leon UNAN Leon, Nicaragua .
    Reyes, Yaoska
    University of Leon UNAN Leon, Nicaragua .
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Predominance of Norovirus and Sapovirus in Nicaragua after Implementation of Universal Rotavirus Vaccination2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 5, p. e0098201-Article in journal (Refereed)
    Abstract [en]

    Background: Despite significant reduction of rotavirus (RV) infections following implementation of RotaTeq vaccination in Nicaragua, a large burden of patients with diarrhea persists. Methods: We conducted a community-and hospital-based study of the burden of RV, norovirus (NV) and sapovirus (SV) infections as cause of sporadic acute gastroenteritis (GE) among 330 children less than= 5 years of age between September 2009 and October 2010 in two major cities of Nicaragua with a RotaTeq coverage rate of 95%. Results: We found that NV, SV and RV infections altogether accounted for 45% of cases of GE. Notably, NV was found in 24% (79/330) of the children, followed by SV (17%, 57/330) and RV (8%, 25/330). The detection rate in the hospital setting was 27%, 15% and 14% for NV, SV and RV respectively, whereas in the community setting the detection rate of RV was less than 1%. Among each of the investigated viruses one particular genogroup or genotype was dominant; GII.4 (82%) for NV, GI (46%) for SV and G1P[8] (64%) in RV. These variants were also found in higher proportions in the hospital setting compared to the community setting. The GII.4.2006 Minerva strain circulating globally since 2006 was the most common among genotyped NV in this study, with the GII.4-2010 New Orleans emerging in 2010. Conclusions: This study shows that NV has become the leading viral cause of gastroenteritis at hospital and community settings in Nicaragua after implementation of RV vaccination.

  • 25.
    Istrate, Claudia
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Vikström, Elena
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Magnusson, Karl-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Rotavirus Infection Increases Intestinal Motility but Not Permeability at the Onset of Diarrhea2014In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 88, no 6, p. 3161-3169Article in journal (Refereed)
    Abstract [en]

    The disease mechanisms associated with onset and secondary effects of rotavirus (RV) diarrhea remain to be determined and may not be identical. In this study, we investigated whether onset of RV diarrhea is associated with increased intestinal permeability and/or motility. To study the transit time, fluorescent fluorescein isothiocyanate (FITC)-dextran was given to RV-infected adult and infant mice. Intestinal motility was also studied with an opioid receptor agonist (loperamide) and a muscarinic receptor antagonist (atropine). To investigate whether RV increases permeability at the onset of diarrhea, fluorescent 4- and 10-kDa dextran doses were given to infected and noninfected mice, and fluorescence intensity was measured subsequently in serum. RV increased transit time in infant mice. Increased motility was detected at 24 h postinfection (h p.i.) and persisted up to 72 h p.i in pups. Both loperamide and atropine decreased intestinal motility and attenuated diarrhea. Analysis of passage of fluorescent dextran from the intestine into serum indicated unaffected intestinal permeability at the onset of diarrhea (24 to 48 h p.i.). We show that RV-induced diarrhea is associated with increased intestinal motility via an activation of the myenteric nerve plexus, which in turn stimulates muscarinic receptors on intestinal smooth muscles.

  • 26.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Nitiema, Léon W
    Centre de Recherche Biomoléculaire Pietro Annigoni Saint Camille CERBA/LABIOGENE, Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Ouermi, Djeneba
    Centre de Recherche Biomoléculaire Pietro Annigoni Saint Camille CERBA/LABIOGENE, Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Simpore, Jacques
    Centre de Recherche Biomoléculaire Pietro Annigoni Saint Camille CERBA/LABIOGENE, Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Host Genetic Factors Affect Susceptibility to Norovirus Infections in Burkina Faso2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 7, p. e69557-Article in journal (Refereed)
    Abstract [en]

    Norovirus (NoV) constitutes the second most common viral pathogen causing pediatric diarrhea after rotavirus. In Africa, diarrhea is a major health problem in children, and yet few studies have been performed regarding NoV. The association of histo-blood group antigens (HBGA) and susceptibility to NoV infection is well established in Caucasian populations with non-secretors being resistant to many common NoV strains. No study regarding HBGA and NoV susceptibility has yet been performed in Africa. We collected 309 stool and 208 saliva samples from diarrheal children in Ouagadougou, Burkina Faso; May 2009 to March 2010. NoV was detected using real-time PCR, and genotyped by sequencing. Saliva samples were ABO, Lewis and secretor phenotyped using in house ELISA assays. NoV was detected in 12% (n = 37) of the samples. The genotype diversity was unusually large; overall the 37 positive samples belonged to 14 genotypes. Only children <2 years of age were NoV positive and the GII.4 NoVs were more frequent in the late dry season (Jan-May). NoV infections were observed less in children with the secretor-negative phenotype or blood group A (OR 0.18; p = 0.012 and OR 0.31; p = 0.054; respectively), with two non-secretors infected with genotypes GII.7 and GII.4 respectively. Lewis-negative (Lea−b−) children, representing 32% of the study population, were susceptible to GII, but were not infected with any NoV GI. GII.4 strains preferentially infected children with blood group B whereas secretor-positive children with blood group O were infected with the largest variety of genotypes. This is the first study identifying host genetic factors associated with susceptibility to NoV in an African population, and suggests that while the non-secretor phenotype provides protection; the Lewis b antigen is not necessary for GII infection.

  • 27.
    Rydell, G E
    et al.
    Institut Curie, Centre de Recherche, Traffic, Signaling and Delivery Group, 26 rue d'Ulm, F-75248 Paris Cedex 05, France; CNRS UMR144, France.
    Svensson, Lennart
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Larson, G
    Dept. of Clinical Chemistry and Transfusion Medicine, Sahlgrenska Academy at the University of Gothenburg, SE-413 45 Sweden.
    Johannes, L
    Institut Curie, Centre de Recherche, Traffic, Signaling and Delivery Group, 26 rue d'Ulm, F-75248 Paris Cedex 05, France; CNRS UMR144, France.
    Römer, W
    CNRS UMR144, France; Institute of Biology II, University of Freiburg, Schänzlestraβe 1, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Synthetic Biology of Signalling Processes Group, University of Freiburg, Schänzlestraβe 18, 79104 Freiburg, Germany.
    Human GII.4 norovirus VLP induces membrane invaginations on giant unilamellar vesicles containing secretor gene dependent α1,2-fucosylated glycosphingolipids.2013In: Biochimica et Biophysica Acta - Biomembranes, ISSN 0005-2736, E-ISSN 1879-2642, Vol. 1828, no 8, p. 1840-5Article in journal (Refereed)
    Abstract [en]

    Norovirus is a non-enveloped virus causing acute gastroenteritis. For human norovirus, no simple cell culture system is available and consequently knowledge on cellular entry of the virus is limited. The virus binds to ABH histo-blood group glycans on glycoproteins and glycosphingolipids. Non-secretors, characterized by the lack of ABH histo-blood group glycans in the gastrointestinal tract, are resistant to most norovirus infections, suggesting that these glycans may be part of the viral receptor. Recent studies have shown that polyomavirus enters the cell via membrane invaginations induced by the multivalent binding of the virus to receptor glycosphingolipids. In this study, we have investigated whether norovirus has the ability to induce membrane invaginations on giant unilamellar vesicles (GUVs) containing purified glycosphingolipids. First, we characterized the glycosphingolipid binding pattern of VLPs from the Dijon strain (genogroup II.4), using thin-layer chromatography. The VLP recognized the ABH active glycosphingolipids H type 1, Lewis b, B type 1, A type 1 and A Lewis b, but not lactotetraosylceramide or Lewis a, typically found in non-secretors. The binding pattern to glycosphingolipids incorporated into GUVs was in full agreement with the thin-layer chromatography experiments. Upon binding to the vesicles, the VLPs formed highly mobile clusters on the surface of the GUVs. VLP containing tubular invaginations were seen on the GUVs containing glycosphingolipids recognized by the VLP. In conclusion, this study suggests that human norovirus has the ability to induce membrane curvature by binding to and clustering glycosphingolipids, which may reflect the first step in cellular entry of the virus.

  • 28.
    Günaydın, Gökçe
    et al.
    Division of Clinical Immunology, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden.
    Nordgren, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Svensson, Lennart
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Hammarström, Lennart
    Division of Clinical Immunology, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden.
    TLR3-dependent antibody response against rotavirus in individuals with immunoglobulin A deficiency2013In: Journal of Infectious Diseases, ISSN 0022-1899, E-ISSN 1537-6613Article in journal (Refereed)
  • 29.
    Jonsson, Nina
    et al.
    Linnaeus University, Sweden .
    Wahlström, Kristin
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Serrander, Lena
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Lindberg, A. Michael
    Linnaeus University, Sweden .
    Aichi virus infection in elderly people in Sweden2012In: Archives of Virology, ISSN 0304-8608, E-ISSN 1432-8798, Vol. 157, no 7, p. 1365-1369Article in journal (Refereed)
    Abstract [en]

    Aichi virus (AiV), genus Kobuvirus, family Picornaviridae, is associated with gastroenteritis in humans. Previous studies have shown high seroprevalence but low incidence (0.9-4.1%) in clinical samples. We report here the first detection of AiV in Sweden. Two hundred twenty-one specimens from hospitalized patients with diarrhea, who were negative for other enteric viruses, were included in the study. AiV were detected in three specimens, all from elderly patients. Phylogenetic analysis revealed that the three Swedish isolates belonged to genotype A and were genetically closest to European and Asian strains of AiV.

  • 30.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Nitiema, Leon W
    University of Ouagadougou.
    Sharma, Sumit
    University of Ouagadougou.
    S Traore, Alfred
    University of Ouagadougou.
    Simpore, Jacques
    University of Ouagadougou.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Emergence of Unusual G6P[6] Rotaviruses in Children, Burkina Faso, 2009-20102012In: Emerging Infectious Diseases, ISSN 1080-6040, E-ISSN 1080-6059, Vol. 18, no 4, p. 589-597Article in journal (Refereed)
    Abstract [en]

    To obtain more information about rotavirus (ROTAV) genotypes in Burkina Faso, we characterized 100 ROTAVs isolated from fecal samples of children with acute gastroenteritis in the capital city of Ouagadougou, during December 2009 March 2010. Of note, 13% of the ROTAV-positive samples, including those with mixed infections, were positive for the unusual G6 genotype ROTAV strain. The genotypes identified were G9P[8], G6P[6], G1P[6], G3P[6], G1P[8], and G2P[4]. G9P[8] subgroup (SG) II strains dominated during the beginning of the ROTAV season, but later in the season, other G types associated with P[6] and SGI specificity emerged. This emergence was related to a shift in the overall age of infected children; ROTAV SGII infected younger children and induced more severe symptoms. The finding of a high incidence of G6P[6] strains highlights the need for long-term surveillance of ROTAV strains in Burkina Faso, especially when ROTAV vaccination is being considered in several African countries.

  • 31.
    Oluwatoyin Japhet, Margaret
    et al.
    Obafemi Awolowo University, Nigeria .
    Adeyemi Adesina, Olufisayo
    Obafemi Awolowo University, Nigeria .
    Famurewa, Oladiran
    Ekiti State University, Nigeria .
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Molecular epidemiology of rotavirus and norovirus in Ile-Ife, Nigeria: High prevalence of G12P[8] rotavirus strains and detection of a rare norovirus genotype2012In: Journal of Medical Virology, ISSN 0146-6615, E-ISSN 1096-9071, Vol. 84, no 9, p. 1489-1496Article in journal (Refereed)
    Abstract [en]

    Rotavirus (RV) and norovirus (NoV) are considered the most common causes of viral gastroenteritis in children. In this study, the prevalence of RV and NoV infection in 55 children with diarrhea from the rural community Akinlalu in Southwestern Nigeria was investigated using real-time PCR assays. The RV and NoV strains were genotyped by PCR and/or sequencing. RV and NoV infections occurred with a prevalence of 34.5% and 25.5% respectively, with predominance in children andlt;1 year. Most infections occurred during the dry season with increasing prevalence of RV as the dry season progressed (OctoberJanuary). Infections with RV VP6 subgroup (SG) II were more prevalent (27.3%) than SGI (7.3%). Similarly, NoV genogroup II infections were more common (23.6%) than genogroup I (1.8%). Five children out of 55 (9.1%) were co-infected with both RV and NoV. Notably, G12P[8] was the predominant RV strain (36.8%, n?=?7), observed for the first time in Nigeria. The VP7 gene of the G12 strains clustered within lineage III, sharing high nucleotide identity with each other (andgt;99%) indicating introduction in Nigeria from a single donor. Furthermore, a putative novel genotype within genogroup I NoV was detected, which till date has only been reported once in humans. To conclude, a high prevalence of the emerging G12P[8] RV strain was observed for the first time in Nigeria, as well as a putative novel NoV genotype in humans. These results provide new information which can be important for future vaccine evaluations and possible introduction in Nigeria.

  • 32.
    Bally, Marta
    et al.
    Chalmers, Sweden .
    Rydell, Gustaf E.
    Institute Curie, France .
    Zahn, Raphael
    University of Zurich, Switzerland Swiss Federal Institute Technology, Switzerland .
    Nasir, Waqas
    University of Gothenburg, Sweden .
    Eggeling, Christian
    Max Planck Institute Biophys Chemistry, Germany .
    Breimer, Michael E.
    University of Gothenburg, Sweden .
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Hook, Fredrik
    Chalmers, Sweden .
    Larson, Gran
    University of Gothenburg, Sweden .
    Norovirus GII.4 Virus-like Particles Recognize Galactosylceramides in Domains of Planar Supported Lipid Bilayers2012In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 51, no 48, p. 12020-12024Article in journal (Refereed)
    Abstract [en]

    n/a

  • 33.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Juste O Bonkoungou, Isidore
    Laboratoire National de Santé Publique du Burkina Faso, Ouagadougou, Burkina Faso, Laboratoire de Biologie Moléculaire, d’Epidémiologie et Surveillance des Bactéries et Virus Transmissibles par les Aliments, CRSBAN/UFR-SVT, Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Nitiema, Leon W.
    Centre de Recherche Biomoléculaire Pietro Annigoni, Saint Camille CERBA/LABIOGENE, Université de Ouagadougou, Ouagadougou, Burkina Faso, Centre de Recherche en Sciences Biologiques, Alimentaires et Nutritionnelles (CRSBAN), Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Ouermi, Djeneba
    Centre de Recherche Biomoléculaire Pietro Annigoni, Saint Camille CERBA/LABIOGENE, Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Simpore, Jacques
    Centre de Recherche Biomoléculaire Pietro Annigoni, Saint Camille CERBA/LABIOGENE, Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Barro, Nicolas
    Laboratoire de Biologie Moléculaire, d’Epidémiologie et Surveillance des Bactéries et Virus Transmissibles par les Aliments, CRSBAN/UFR-SVT, Université de Ouagadougou, Ouagadougou, Burkina Faso.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Rotavirus in diarrheal children in rural Burkina Faso: High prevalence of genotype G6P[6]2012In: Infection, Genetics and Evolution, ISSN 1567-1348, E-ISSN 1567-7257, Vol. 12, no 8, p. 1892-1898Article in journal (Refereed)
    Abstract [en]

    Group A rotavirus (RVA) is the most common cause of severe gastroenteritis in young children globally, and responsible for a significant number of deaths in African countries. While vaccines are available, trials have shown a lesser efficacy in Africa. One of the reasons could be the prevalence and/or emergence of unusual or novel RVA strains, as many strains detected in African countries remain uncharacterized. less thanbrgreater than less thanbrgreater thanIn this study, we characterized RVA positive specimens from two remote rural areas in Burkina Faso, West Africa. In total 56 RVA positive specimens were subgrouped by their VP6 gene, and G-and P typed by PCR and/or sequencing of the VP7 and VP4 genes, respectively. less thanbrgreater than less thanbrgreater thanNotably, we found a high prevalence of the unusual G6P[6]SGI strains (23%). It was the second most common constellation after G9P[8]SGII (32%); and followed by G1P[8]SGII (20%) and G2P[4]SGI (9%). We also detected a G8P[6]SGI strain, for the first time in Burkina Faso. The intra-genetic diversity was high for the VP4 gene with two subclusters within the P[8] genotype and three subclusters within the P[6] genotype which were each associated with a specific G-type, thereby suggesting a genetic linkage. The G6P[6]SGI and other SGI RVA strains infected younger children as compared to SGII strains (p andlt; 0.05). less thanbrgreater than less thanbrgreater thanTo conclude, in this study we observed the emergence of unusual RVA strains and high genetic diversity of RVA in remote rural areas of Burkina Faso. The results highlight the complexity of RVA epidemiology which may have implication for the introduction of rotavirus vaccines currently being evaluated in many African countries.

  • 34.
    Bucardo, Filemon
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences. Department of Microbiology, University of León, UNAN-León, Nicaragua.
    Carlsson, Beatrice
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Larson, Göran
    University of Gothenburg, Göteborg, Sweden.
    Blandon, Patricia
    Department of Microbiology University of León, Nicaragua (UNAN-León).
    Vilchez, Samuel
    Department of Microbiology University of León, Nicaragua (UNAN-León).
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Susceptibility of Children to Sapovirus Infections, Nicaragua, 2005–20062012In: Emerging Infectious Diseases, ISSN 1080-6040, E-ISSN 1080-6059, Vol. 18, no 11, p. 1875-1878Article in journal (Refereed)
    Abstract [en]

    We describe the genetic diversity of sapovirus (SaV) in children in Nicaragua and investigate the role of host genetic factors and susceptibility to SaV infections. Our results indicate that neither ABO blood group, Lewis phenotype, nor secretor status affects susceptibility to SaV infection in Nicaragua.

  • 35.
    Hagbom, Marie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Lundgren, Ove
    Gothenburg University, Sweden .
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Towards a human rotavirus disease model2012In: CURRENT OPINION IN VIROLOGY, ISSN 1879-6257, Vol. 2, no 4, p. 408-418Article in journal (Refereed)
    Abstract [en]

    While the clinical importance of human rotavirus (RV) disease is well recognized and potent vaccines have been developed, our understanding of how human RV causes diarrhoea, vomiting and death remains unresolved. The fact that oral rehydration corrects electrolyte and water loss, indicates that enterocytes in the small intestine have a functional sodium-glucose co-transporter. Moreover, RV infection delays gastric emptying and loperamide appears to attenuate RV diarrhoea, thereby suggesting activation of the enteric nervous system. Serotonin (5-HT) receptor antagonists attenuate vomiting in young children with gastroenteritis while zinc and enkephalinase inhibitors attenuate RV-induced diarrhoea. In this review we discuss clinical symptoms, pathology, histology and treatment practices for human RV infections and compile the data into a simplified disease model.

  • 36.
    Bucardo, Filemon
    et al.
    University of Leon, Nicaragua .
    Rippinger, Christine M.
    NIAID, USA .
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Patton, John T.
    NIAID, USA .
    Vaccine-derived NSP2 segment in rotaviruses from vaccinated children with gastroenteritis in Nicaragua2012In: Infection, Genetics and Evolution, ISSN 1567-1348, E-ISSN 1567-7257, Vol. 12, no 6, p. 1282-1294Article in journal (Refereed)
    Abstract [en]

    Rotavirus (RV) vaccination programs have been established in several countries using the human-attenuated G1P[8] monovalent vaccine Rotarix (TM) (GlaxoSmithKline) and/or the human-bovine reassortant G1, G2, G3, G4, P[8] pentavalent vaccine Rotaleq (TM) (Merck). The efficacy of both vaccines is high (similar to 90%) in developed countries, but can be remarkably lower in developing countries. For example, a vaccine efficacy against severe diarrhea of only 58% was observed in a 2007-2009 Nicaraguan study using RotaTeq. To gain insight into the significant level of vaccine failure in this country, we sequenced the genomes of RVs recovered from vaccinated Nicaraguan children with gastroenteritis. The results revealed that all had genotype specificities typical for human RVs (11G1P[8], 1G3P[8]) and that the sequences and antigenic epitopes of the outer capsid proteins (VP4 and VP7) of these viruses were similar to those reported for RVs isolated elsewhere in the world. As expected, nine of the G1 P[8] viruses and the single G3P[8] virus had genome constellations typical of human G1 P[8] and G3P[8] RVs: G1/3-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1. However, two of the G1P[8] viruses had atypical constellations, G1-P[8]-I1-R1-C1-M1-A1-N2-T1-E1-H1, due to the presence of a genotype-2 NSP2 (N2) gene. The sequence of the N2 NSP2 gene was identical to the bovine N2 NSP2 gene of RotaTeq, indicating that the two atypical viruses originated via reassortment of human G1P[8] RVs with RotaTeq viruses. Together, our data suggest that the high level of vaccine failure in Nicaraguan is probably not due to antigenic drift of commonly circulating virus strains nor the emergence of new antigenetically distinct virus strains. Furthermore, our data suggest that the widespread use of the RotaTeq vaccine has led to the introduction of vaccine genes into circulating human RVs.

  • 37.
    Kindberg, Elin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Vene, Sirkka
    Swedish Institute Infectious Disease Control.
    Mickiene, Aukse
    Kaunas University of Medicine.
    Lundkvist, Ake
    Swedish Institute Infectious Disease Control.
    Lindquist, Lars
    Karolinska University.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    A Functional Toll-Like Receptor 3 Gene (TLR3) May Be a Risk Factor for Tick-borne Encephalitis Virus (TBEV) Infection2011In: JOURNAL OF INFECTIOUS DISEASES, ISSN 0022-1899, Vol. 203, no 4, p. 523-528Article in journal (Refereed)
    Abstract [en]

    Background. Tick-borne encephalitis virus (TBEV) infections may be asymptomatic or cause severe symptoms in the central nervous system. A mutation in the chemokine receptor 5 gene has been associated with increased risk of TBE but explains only a limited number of cases. Investigations of further risk factors are needed. Method. To investigate the importance of the innate immune response, we analyzed 128 TBE patients, 77 patients with aseptic meningoencephalitis (AME) and 135 healthy controls, for 3mutations: 2 in the Toll-like receptor 3 (TLR3) gene and 1 in the 2-5-oligoadenylate synthetase (OAS1) gene. Results. Although no association was found between the mutation in the OAS1 gene and TBE, the genotype distribution ofrs3775291, a mutation in TLR3, differed significantly between TBE patients and controls; 61%, 32%, and 7% of the TBE patients were carriers of the wild-type, heterozygous, and mutant genotype of rs3775291, respectively. The corresponding percentages among healthy controls (n = 126) were 52%, 29%, and 19% (P = .02), and among AME patients (n = 75) were 47%, 32%, and 21% (P = .009). Additionally, the wild-type rs3775291 allele was more common among TBE patients than among healthy controls (allele frequency, .768 vs .663; P = .01). Conclusion. A functional TLR3 is a risk factor for TBEV infection.

  • 38.
    Nitiema, Leon W
    et al.
    University of Ouagadougou.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Ouermi, Djeneba
    University of Ouagadougou.
    Dianou, Dayeri
    Centre for National Resarch Science and Technology, Ouagadougou.
    Traore, Alfred S
    University of Ouagadougou.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Simpore, Jacques
    University of Ouagadougou.
    Burden of rotavirus and other enteropathogens among children with diarrhea in Burkina Faso2011In: International Journal of Infectious Diseases, ISSN 1201-9712, E-ISSN 1878-3511, Vol. 15, no 9, p. E646-E652Article in journal (Refereed)
    Abstract [en]

    Objective: There is limited information available regarding the etiology of gastrointestinal infections in Burkina Faso. The aim of this study was to investigate the prevalence and epidemiology of enteric pathogens causing gastroenteritis in young children, with a focus on rotavirus, and to investigate the levels of malnutrition and other clinical factors in association with the severity of diarrhea. less thanbrgreater than less thanbrgreater thanMethods: A prospective study was undertaken from May 2009 to March 2010, covering the rainy and dry seasons, at the Saint Camille Medical Center in Ouagadougou, Burkina Faso. A total of 309 children less than 5 years of age with diarrhea were enrolled and examined for rotavirus, bacterial, and parasitic infections, as well as clinico-epidemiological aspects. less thanbrgreater than less thanbrgreater thanResults: At least one enteropathogen was detected in 57.9% (n = 179) of the children. Of these, 32.4% had rotavirus infections, 16.8% bacterial infections (enteropathogenic Escherichia coli 9.7%, Shigella spp 5.8%, and Salmonella spp 2.3%), and 18.8% parasitic infections (Giardia lamblia 11.3%, Trichomonas intestinalis 6.8%, Entamoeba histolytica/dispar 1.3%). During the cold dry period from December 2009 to February 2010, we observed a large increase in diarrhea cases, which was mainly attributed to rotavirus infections, as 63.8% of these diarrhea cases were positive for rotavirus. In contrast, no rotavirus infection was observed during the rainy season (June-September 2009), when the frequency of parasitic infections was high. Rotavirus and parasitic infections were age-related, with rotavirus being more prevalent in young children (andlt;12 months) and parasites more common in older children (andgt;12 months), while bacteria were equally prevalent among all age groups. Rotavirus infections exhibited more severe symptoms compared to bacteria and parasites, and were associated with fever, vomiting, and severe dehydration. Malnutrition, especially acute malnutrition (wasting), was significantly associated with more severe symptoms in rotavirus-induced diarrhea. The undernourished children also exhibited a prolonged duration of diarrheal episodes. less thanbrgreater than less thanbrgreater thanConclusion: This study demonstrates rotavirus as the main etiological agent in pediatric diarrhea in Burkina Faso, and further shows the great severity of rotavirus-induced diarrhea in undernourished children in Burkina Faso.

  • 39.
    Bally, M
    et al.
    Chalmers.
    Gunnarsson, A
    Chalmers.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Larson, G
    University of Gothenburg.
    Zhdanov, V P
    Chalmers.
    Hook, F
    Chalmers.
    Interaction of Single Viruslike Particles with Vesicles Containing Glycosphingolipids2011In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 107, no 18, p. 188103-Article in journal (Refereed)
    Abstract [en]

    Glycosphingolipids are involved in the first steps of virus-cell interaction, where they mediate specific recognition of the host cell membrane. We have employed total-internal-reflection fluorescence microscopy to explore the interaction kinetics between individual unlabeled noroviruslike particles, which are attached to a glycosphingolipid-containing lipid bilayer, and fluorescent vesicles containing different types and concentrations of glycosphingolipids. Under association equilibrium, the vesicle-binding rate is found to be kinetically limited, yielding information on the corresponding activation energy. The dissociation kinetics are logarithmic over a wide range of time. The latter is explained by the vesicle-size-related distribution of the dissociation activation energy. The biological, pharmaceutical, and diagnostic relevance of the study is briefly discussed.

  • 40.
    Lundgren, Ove
    et al.
    University of Gothenburg.
    Jodal, Mats
    University of Gothenburg.
    Jansson, Madeleine
    University of Gothenburg.
    T Ryberg, Anders
    University of Gothenburg.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Intestinal Epithelial Stem/Progenitor Cells Are Controlled by Mucosal Afferent Nerves2011In: PLOS ONE, ISSN 1932-6203, Vol. 6, no 2, p. 16295-Article in journal (Refereed)
    Abstract [en]

    Background: The maintenance of the intestinal epithelium is of great importance for the survival of the organism. A possible nervous control of epithelial cell renewal was studied in rats and mice. Methods: Mucosal afferent nerves were stimulated by exposing the intestinal mucosa to capsaicin (1.6 mM), which stimulates intestinal external axons. Epithelial cell renewal was investigated in the jejunum by measuring intestinal thymidine kinase (TK) activity, intestinal H-3-thymidine incorporation into DNA, and the number of crypt cells labeled with BrdU. The influence of the external gut innervation was minimized by severing the periarterial nerves. Principal Findings: Luminal capsaicin increased all the studied variables, an effect nervously mediated to judge from inhibitory effects on TK activity or H-3-thymidine incorporation into DNA by exposing the mucosa to lidocaine (a local anesthetic) or by giving four different neurotransmitter receptor antagonists i.v. (muscarinic, nicotinic, neurokinin1 (NK1) or calcitonin gene related peptide (CGRP) receptors). After degeneration of the intestinal external nerves capsaicin did not increase TK activity, suggesting the involvement of an axon reflex. Intra-arterial infusion of Substance P (SP) or CGRP increased intestinal TK activity, a response abolished by muscarinic receptor blockade. Immunohistochemistry suggested presence of M3 and M5 muscarinic receptors on the intestinal stem/progenitor cells. We propose that the stem/progenitor cells are controlled by cholinergic nerves, which, in turn, are influenced by mucosal afferent neuron(s) releasing acetylcholine and/or SP and/or CGRP. In mice lacking the capsaicin receptor, thymidine incorporation into DNA and number of crypt cells labeled with BrdU was lower than in wild type animals suggesting that nerves are important also in the absence of luminal capsaicin, a conclusion also supported by the observation that atropine lowered thymidine incorporation into DNA by 60% in control rat segments. Conclusion: Enteric nerves are of importance in maintaining the intestinal epithelial barrier.

  • 41.
    Bucardo, Filemon
    et al.
    University of Leon.
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Low Prevalence of Rotavirus and High Prevalence of Norovirus in Hospital and Community Wastewater after Introduction of Rotavirus Vaccine in Nicaragua2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 10Article in journal (Refereed)
    Abstract [en]

    Rotavirus (RV) and norovirus (NoV) are major causes of pediatric diarrhea and are altogether associated with approximately 800,000 deaths in young children every year. In Nicaragua, national RV vaccination program using the pentavalent RV5 vaccine from Merck was implemented in October 2006. To determine whether RV vaccination decreased the overall number of RV infections, we investigated the occurrence of RV and NoV in wastewater in the city of Leon from July 2007 to July 2008 and compared these data with pre-vaccination data. The major finding was the low prevalence of RV compared to NoV in all sampling points (11% vs 44%, pandlt;0.05), and that RV concentration was lower as compared to NoV. RV was observed mainly during the rainy season (July-September), and the majority of all RV detected (6/9) belonged to subgroup (SG) I. The partial VP7-gene obtained from one RV positive sample was similar (99% nt identity) to a G6 VP7-gene of bovine origin and similar to the corresponding gene of the vaccine strain (98%). Furthermore RV G-types 2 and 4 were found in the incoming wastewater. NoV strains were detected throughout the year, of which a majority (20/21) were of genotype GII.4. We conclude that the introduction of RV vaccination reduced the transmission of RV in the community in Nicaragua. However, the burden of diarrhea in the country remains high, and the high prevalence of NoVs in hospital and municipal wastewater is noteworthy. This study highlights the need for further assessment of NoV following RV vaccine introduction.

  • 42.
    Hagbom, Marie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Istrate, Claudia
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology.
    Engblom, David
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Karlsson, Thommie
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology.
    Rodriguez-Diaz, Jesus
    University of Valencia.
    Buesa, Javier
    University of Valencia.
    Taylor, John A
    University of Auckland.
    Loitto, Vesa
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Magnusson, Karl-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Ahlman, Hakan
    University of Gothenburg.
    Lundgren, Ove
    University of Gothenburg.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting2011In: PLOS PATHOGENS, ISSN 1553-7366, Vol. 7, no 7Article in journal (Refereed)
    Abstract [en]

    otavirus (RV) is the major cause of severe gastroenteritis in young children. A virus-encoded enterotoxin, NSP4 is proposed to play a major role in causing RV diarrhoea but how RV can induce emesis, a hallmark of the illness, remains unresolved. In this study we have addressed the hypothesis that RV-induced secretion of serotonin (5-hydroxytryptamine, 5-HT) by enterochromaffin (EC) cells plays a key role in the emetic reflex during RV infection resulting in activation of vagal afferent nerves connected to nucleus of the solitary tract (NTS) and area postrema in the brain stem, structures associated with nausea and vomiting. Our experiments revealed that RV can infect and replicate in human EC tumor cells ex vivo and in vitro and are localized to both EC cells and infected enterocytes in the close vicinity of EC cells in the jejunum of infected mice. Purified NSP4, but not purified virus particles, evoked release of 5-HT within 60 minutes and increased the intracellular Ca(2+) concentration in a human midgut carcinoid EC cell line (GOT1) and ex vivo in human primary carcinoid EC cells concomitant with the release of 5-HT. Furthermore, NSP4 stimulated a modest production of inositol 1,4,5-triphosphate (IP(3)), but not of cAMP. RV infection in mice induced Fos expression in the NTS, as seen in animals which vomit after administration of chemotherapeutic drugs. The demonstration that RV can stimulate EC cells leads us to propose that RV disease includes participation of 5-HT, EC cells, the enteric nervous system and activation of vagal afferent nerves to brain structures associated with nausea and vomiting. This hypothesis is supported by treating vomiting in children with acute gastroenteritis with 5-HT(3) receptor antagonists.

  • 43.
    Rydell, Gustaf E
    et al.
    University of Gothenburg.
    Kindberg, Elin
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Larson, Goeran
    University of Gothenburg.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Susceptibility to winter vomiting disease: a sweet matter2011In: Reviews in Medical Virology, ISSN 1052-9276, E-ISSN 1099-1654, Vol. 21, no 6, p. 370-382Article, review/survey (Refereed)
    Abstract [en]

    Norovirus, the cause of winter vomiting disease, has emerged in recent years to be a major cause of sporadic and epidemic gastroenteritis worldwide. The virus has been estimated to cause andgt;200 000 deaths each year in developing countries. Although the virus is highly contagious, volunteer and field studies have shown that a subset of individuals appears resistant to infections. A single nucleotide mutation (G428A) in the fucosyltransferase gene (FUT2) on chromosome 19 provides strong protection from infection in 20% of the white population. Histo-blood group ABO(H) antigens with terminal fucose are believed to function as receptors for human norovirus in the gastrointestinal tract, but also negatively charged potential receptors have been identified. Norovirus infection is a unique example where a single nucleotide mutation in a fucosyltransferase gene plays a crucial role in susceptibility to one of the most common viral diseases. This review discusses the role of host genetics and carbohydrate structures in susceptibility to winter vomiting disease.

  • 44.
    Bucardo, Filemon
    et al.
    University of Leon.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Paniagua, Margarita
    University of Leon.
    Mollby, Roland
    Karolinska Institute.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Asymptomatic Norovirus Infections in Nicaraguan Children and its Association With Viral Properties and Histo-blood Group Antigens2010In: PEDIATRIC INFECTIOUS DISEASE JOURNAL, ISSN 0891-3668, Vol. 29, no 10, p. 934-939Article in journal (Refereed)
    Abstract [en]

    Background: It has been previously reported that histo-blood group antigens (HBGAs) and particularly secretor status provides protection against symptomatic norovirus infection, but it remains unclear to what extent this includes asymptomatic infections in children. Methods: To explore whether HBGAs or certain viral genotypes are associated with asymptomatic norovirus infections in a pediatric population in Nicaragua, we investigated 163 children andlt;= 5 years of age, without a recent history of diarrhea (andlt;= 10 days). Results: Asymptomatic norovirus infections were observed in 11.7% (19/163), with children andlt;= 6 months of age being most frequently infected (16%). Of the 19 norovirus-positive children, 4 (21%) and 10 (53%) were infected with genogroups GI and GII, respectively, and 4 children (21%) were infected with viruses of both genogroups. Most children had andgt;= 10(6) viral genomes per gram of feces. Nucleotide sequence analysis (15/19) revealed uncommon genotypes, such as, GII. 7 (n = 5) and GII. 2 (n = 3). An interesting observation was the low frequency of norovirus GII. 4 strains among the asymptomatic children. AB blood type, Lewis a (Lea(a+b-)) phenotype and nonsecretor genotype (se(428)se(428)) were not found among the asymptomatic children, but they occurred in population controls. Conclusions: Frequency of asymptomatic norovirus infections was similar to that observed in symptomatic children from Nicaragua. Norovirus GII. 2 and GII. 7 were frequently detected but the globally dominating GII. 4 was infrequent. Host genetic factors previously observed to be associated with protection against symptomatic norovirus infection were not found in this study.

  • 45.
    Vildevall, Malin
    et al.
    Sahlgrensha University Hospital.
    Oliver, Stefan L
    University of London Royal Veterinary College.
    Bridger, Janice C
    University of London Royal Veterinary College.
    Charpilienne, Annie
    CNRS.
    Poncet, Didier
    CNRS.
    Larson, Goran
    Sahlgrensha University Hospital.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Human Antibody Responses to Bovine (Newbury-2) Norovirus (GIII.2) and Association to Histo-Blood Group Antigens2010In: JOURNAL OF MEDICAL VIROLOGY, ISSN 0146-6615, Vol. 82, no 7, p. 1241-1246Article in journal (Refereed)
    Abstract [en]

    Serum antibodies to bovine norovirus have been found recently in about 22% of humans. Whether this prevalence reflects limited virulence properties of the virus or that inherited host factors provide protection against bovine norovirus infection in humans remains to be established. To investigate whether histo-blood group antigens correlate with the presence of bovine norovirus (GIII.2) antibody, plasma (n = 105) from Swedish blood donors, genotyped and phenotyped for secretor, Lewis and ABO, were tested and compared for the frequency of IgG antibody and antibody titer to Bo/Newbury2/76/UK. In total, 26.7% (28/105) of Swedish blood donors were antibody-positive. Two non-secretors (2/21, 9.5%) were antibody-positive compared with 26/84 (31%) secretors (P=0.047). While no statistically significant correlation was found between the frequency of antibodies to bovine norovirus and different ABO blood groups, individuals with blood type B presented the highest frequency of antibodies (37.5%) compared with 0-30% among other blood groups. Individuals with Le(a-b+) had not only higher frequency of antibodies (31.3%) compared with Le(a+b-) (11%) (P=0.068) but also higher antibody titer (P=0.085) although this was not significant statistically. No detectable cross-reaction between bovine GIII.2 and human GII.3 NoV VLP was found with human and animal sera. The results of this study suggest that bovine norovirus infections occur in Sweden and that secretor status but not ABO blood groups is a possible risk factor for infection.

  • 46.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Lindgren, Per-Eric
    County Hospital Ryhov, Jonkoping, Sweden .
    Matussek, Andreas
    County Hospital Ryhov, Jonkoping, Sweden Capio St Gorans Hospital, Stockholm, Sweden .
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Norovirus Gastroenteritis Outbreak with a Secretor-independent Susceptibility Pattern, Sweden2010In: Emerging Infectious Diseases, ISSN 1080-6040, E-ISSN 1080-6059, Vol. 16, no 1, p. 81-87Article in journal (Refereed)
    Abstract [en]

    Norovirus (NoV) is recognized as the commonest cause of acute gastroenteritis among adults. Susceptibility to disease has been associated with histo-blood group antigens and secretor status; nonsecretors are almost completely resistant to disease. We report a foodborne outbreak of GI.3 NoV gastroenteritis that affected 33/83 (40%) persons. Symptomatic disease was as likely to develop in nonsecretors as in secretors (odds ratio [OR] 1.41, 95% confidence interval [CI] 0.46-4.36 vs. OR 0.71, 95% Cl 0.23-2.18, p = 0.57). Moreover, no statistical difference in susceptibility was found between persons of different Lewis or ABO phenotypes. The capsid gene of the outbreak strain shares high amino acid homology with the Kashiwa645 GI.3 strain, previously shown to recognize nonsecretor saliva, as well as synthetic Lewis a. This norovirus outbreak affected persons regardless of secretor status or Lewis or ABO phenotypes.

  • 47.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Bucardo, Filemon
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Novel Light-Upon-Extension Real-Time PCR Assay for Simultaneous Detection, Quantification, and Genogrouping of Group A Rotavirus2010In: JOURNAL OF CLINICAL MICROBIOLOGY, ISSN 0095-1137, Vol. 48, no 5, p. 1859-1865Article in journal (Refereed)
    Abstract [en]

    We have developed a light-upon-extension (LUX) real-time PCR assay for detection, quantification, and genogrouping of group A rotavirus (RV), the most common cause of acute gastroenteritis in children. The LUX system uses a fluorophore attached to one primer and having a self-quenching hairpin structure, making it cost-effective and specific. We designed genogroup-specific primers having different fluorophores, making it possible to differentiate between the two main genogroups of human group A RVs. The assay was applied on clinical stool specimens from Sweden and Central America (n = 196) and compared to immunological and conventional PCR assays. The genogrouping ability was further validated against a subset of clinical specimens, which had been genogrouped using monoclonal antibodies. Our real-time PCR assay detected and quantified all positive specimens (n = 145) and exhibited higher sensitivity than immunological assays and conventional PCR. The assay exhibited a wide dynamic range, detecting from 5 to andgt; 10(7) genes per PCR, resulting in a theoretical lower detection limit of andlt; 10,000 viruses per gram of stool. No cross-reaction was observed with specimens containing norovirus, sapovirus, astrovirus, or adenovirus. In total, 22 (15%) of the positive clinical specimens were identified as genogroup I, 122 (84%) were identified as genogroup II, and 1 specimen was found to contain a mix of both genogroups. All genogroup I-positive specimens were associated with capsid glycoprotein 2 (G2). No significant difference in viral load was found between genogroups or geographic region. The detection and quantification, combined with the genogrouping ability, make this assay a valuable tool both for diagnostics and for molecular epidemiological investigations.

  • 48.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Kindberg, Elin
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Matussek, Andreas
    Department of Clinical Microbiology, Division of Laboratory Medicine, County Hospital Ryhov, Jönköping, Sweden/Department of Clinical Microbiology, Capio Diagnostik AB, Capio St Görans Hospital, Stockholm, Sweden.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    A FUT2 nonsense mutation (G428A) and Lewis-independent norovirus GI.3 outbreak2009Article in journal (Other academic)
    Abstract [en]

    Background: Norovirus (NoV) is recognized as the commonest cause of acute gastroenteritis among adults. Previous studies have shown that histo-blood group antigens (HBGAs) and secretor status are associated with susceptibility to symptomatic NoV infection, with non-secretors being almost completely resistant to disease. Here we report on a food-borne GI.3 NoV outbreak affecting 33/83 (40%) individuals.

    Methods: Secretor status and HBGA expression in saliva were determined with pyrosequencing and ELISA. Virus characterization was performed by sequencing the N/S region and the complete capsid gene.

    Results: A novel observation was that homozygous carriers of the nonsense FUT2 G428A allele were more susceptible to symptomatic infection than secretors (odds ratio [OR] 1.41 vs 0.71). Consistent with this observation was that Lewis a positive b negative (Lea+b-) individuals showed the highest susceptibility (OR 2.42) compared with other Lewis phenotypes. Blood group B was associated with partial protection (OR 0.27). The capsid gene of the outbreak strain exhibits high amino acid homology with the Kashiwa645 GI.3 strain, previously shown to recognize non-secretor saliva.

    Conclusion: We describe for the first time a NoV outbreak with Lea+b- individuals homozygous for the G428A nonsense mutation in the FUT2 gene being more susceptible for disease than secretor-positive individuals.

  • 49.
    Kindberg, Elin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Ax, Cecilia
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Fiore, Lucia
    Ist Super Sanita.
    Svensson , Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Ala67Thr Mutation in the Poliovirus Receptor CD155 is a Potential Risk Factor for Vaccine and Wild-Type Paralytic Poliomyelitis2009In: JOURNAL OF MEDICAL VIROLOGY, ISSN 0146-6615 , Vol. 81, no 5, p. 933-936Article in journal (Refereed)
    Abstract [en]

    Poliovirus infections can be asymptomatic or cause severe paralysis. Why some individuals develop paralytic poliomyelitis is unknown, but a role for host genetic factors has been suggested. To investigate if a polymorphism, Ala67Thr, in the poliovirus receptor, which has been found to facilitate increased resistance against poliovirus-induced cell lysis and apoptosis, is associated with increased risk of paralytic poliomyelitis, poliovirus receptor genotyping was undertaken among Italian subjects with vaccine-associated (n = 9), or with wild-type paralytic poliomyelitis (n = 6), and control subjects (n = 71), using RFLP-PCR and pyrosequencing. Heterozygous poliovirus receptor Ala67Thr genotype was found in 13.3% of the patients with paresis and in 8.5% of the controls (Odds Ratio = 1.667). The frequency of Ala67Thr among the controls is in agreement with earlier published data. It is concluded that the Ala67Thr mutation in the poliovirus receptor is a possible risk factor for the development of vaccine-associated or paralytic poliomyelitis associated with wild-type virus.

  • 50.
    Nordgren, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Bucardo, Filemon
    Department of Microbiology, University of León, León, Nicaragua.
    Dienus, Olaf
    Microbiological Laboratory, Ryhov County Hospital, Jönköping, Sweden.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Correction: Novel Light-Upon-Extension Real-Time PCR Assays for Detection and Quantification of Genogroup I and II Noroviruses in Clinical Specimens (vol 46, pg 164, 2008)2009In: Journal of Clinical Microbiology, ISSN 0095-1137, E-ISSN 1098-660X, Vol. 47, no 4, p. 1285-1285Article in journal (Other academic)
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