liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Prevalence, Diversity, and Load of Borrelia species in Ticks That Have Fed on Humans in Regions of Sweden and Åland Islands, Finland with Different Lyme Borreliosis Incidences
Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
Show others and affiliations
2013 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 11, e81433- p.Article in journal (Refereed) Published
Abstract [en]

The incidence of Lyme borreliosis (LB) in a region may reflect the prevalence of Borrelia in the tick population. Our aim was to investigate if regions with different LB incidences can be distinguished by studying the prevalence and diversity of Borrelia species in their respective tick populations. The Borrelia load in a feeding tick increases with the duration of feeding, which may facilitate a transmission of Borrelia Spirochetes from tick to host. Therefore, we also wanted to investigate how the Borrelia load in ticks that have fed on humans varies with the duration of tick feeding. During 2008 and 2009, ticks that had bitten humans were collected from four regions of Sweden and Finland, regions with expected differences in LB incidence. The duration of tick feeding was estimated and Borrelia were detected and quantified by a quantitative PCR assay followed by species determination. Out of the 2,154 Ixodes ricinus ticks analyzed, 26% were infected with Borrelia and seven species were identified. B. spielmanii was detected for the first time in the regions. The tick populations collected from the four regions exhibited only minor differences in both prevalence and diversity of Borrelia species, indicating that these variables alone cannot explain the regions different LB incidences. The number of Borrelia cells in the infected ticks ranged from fewer than ten to more than a million. We also found a lower number of Borrelia cells in adult female ticks that had fed for more than 36 hours, compared to the number of Borrelia cells found in adult female ticks that had fed for less than 36 hours.

Place, publisher, year, edition, pages
Public Library of Science , 2013. Vol. 8, no 11, e81433- p.
National Category
Medical and Health Sciences
Identifiers
URN: urn:nbn:se:liu:diva-102779DOI: 10.1371/journal.pone.0081433ISI: 000327539800130OAI: oai:DiVA.org:liu-102779DiVA: diva2:683899
Note

Funding Agencies|Medical Research Council of South-East Sweden|FORSS-8967FORSS-12573FORSS-29021FORSS-86911|Swedish Research Council (Medicine)|2011-345|County Council of Ostergotland||Wilhelm and Else Stockmanns Foundation||Angstromlands Kuturstiftelse||EU Interreg IV A|167226|

Available from: 2014-01-07 Created: 2013-12-26 Last updated: 2017-12-06
In thesis
1. A STING from a Tick: Epidemiology, Ecology and Clinical Aspects of Lyme Borreliosis
Open this publication in new window or tab >>A STING from a Tick: Epidemiology, Ecology and Clinical Aspects of Lyme Borreliosis
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Lyme borreliosis (LB) is the most common tick-borne disease in the Northern Hemisphere and the number of LB cases is increasing. The infection is caused by spirochetes belonging to the Borrelia burgdorferi sensu lato complex, and is, in Europe, transmitted to humans by Ixodes ricinus ticks.

To gain a deeper knowledge of the interactions between ticks, humans and Borrelia bacteria, we investigated temporal differences in exposure to tick bites in different parts of Sweden and the Åland Islands, Finland during the years 2008 and 2009. We also investigated the site of tick attachment on the human body and the time it takes for a person to detected and remove such ticks. Furthermore, the distribution of Borrelia species and the number of Borrelia cells in the ticks were investigated. Sera taken from the tick-bitten persons at study inclusion were analyzed for the presence of Borrelia antibodies. Three months later, the clinical outcome and the serological response of the tick-bitten persons were investigated. A total of 2154 I. ricinus ticks and 1546 participants were included in the studies.

Participants were exposed to tick bites between April and November, but temporal and spatial differences in exposure to ticks was found. The majority of the tick bites were caused by nymphs (70%) and most tick bites took place on the legs (50%). The site of tick attachment on the body as well as the age and gender of the participant influenced how soon a tick was detected. The majority of participants removed “their” ticks later than 24 hours of attachment. Of all ticks, 26% was Borrelia-infected, but the prevalence varied between the life stages of the tick and between the studied areas. Six species of the B. burgdorferi sensu lato complex and one Borrelia species that may cause tick-borne relapsing fever were detected. Adult ticks that had fed more than 36 hours contained a lower number of Borrelia cells than adult ticks that had fed less than 36 hours. The seroprevalence among the participants varied between genders as well as between the studied areas. Of all participants, 2% was diagnosed with LB and 2.5% seroconverted without an LB diagnose. A correlation between seroconversion and duration time of tick attachment was found, but the number of Borrelia cells in the tick, did not explain the risk of infection for the bitten person.

A deeper knowledge and a better understanding of the interactions between ticks, humans and Borrelia bacteria may contribute reducing the risk for tick bites and the risk of developing LB after a tick bite.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2014. 130 p.
Series
Linköping University Medical Dissertations, ISSN 0345-0082 ; 1385
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-105476 (URN)10.3384/diss.diva-105476 (DOI)978-91-7519-460-8 (ISBN)
Public defence
2014-04-24, Berzeliussalen, Campus US, Linköpings universitet, Linköping, 09:00 (English)
Opponent
Supervisors
Available from: 2014-03-25 Created: 2014-03-25 Last updated: 2014-04-04Bibliographically approved

Open Access in DiVA

fulltext(1436 kB)153 downloads
File information
File name FULLTEXT01.pdfFile size 1436 kBChecksum SHA-512
b99f186c3af16feffd61dc5c5c074b66cf8f5ed7ad59b3b8cc0c9b8a9ea2a44b22bac63e6c3199f7fd0da5df48f2c628832a0bbf03a1744478d290386552e7a5
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Authority records BETA

Wilhelmsson, PeterLindblom, PontusFryland, LindaErnerudh, JanForsberg, PiaLindgren, Per-Eric

Search in DiVA

By author/editor
Wilhelmsson, PeterLindblom, PontusFryland, LindaErnerudh, JanForsberg, PiaLindgren, Per-Eric
By organisation
Division of Microbiology and Molecular MedicineFaculty of Health SciencesDivision of Inflammation MedicineDepartment of Clinical Immunology and Transfusion MedicineDepartment of Infectious Diseases
In the same journal
PLoS ONE
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 153 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 231 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf