A prospective study on the incidence of Borrelia infection after a tick bite in Sweden and on the Åland Islands, Finland (2008-2009)
2016 (English)In: Ticks and Tick-borne Diseases, ISSN 1877-959X, E-ISSN 1877-9603, Vol. 7, no 1, 71-79 p.Article in journal (Refereed) Published
Lyme borreliosis (LB) is a common and increasing tick-borne disease in Europe. The risk of acquiring a Borrelia infection after a tick bite is not fully known. Therefore, we investigated the incidence of Borrelia infection after a tick bite and if the Borrelia load and/or the duration of tick-feeding influenced the risk of infection. During 2008-2009, ticks and blood samples were collected from 1546 tick-bitten persons from Sweden and the Åland Islands, Finland. Follow-up blood samples were taken three months after the tick bite. The duration of tick feeding was microscopically estimated and Borrelia was detected and quantified in ticks by real-time PCR. Anti-Borrelia antibodies were detected in sera using ELISA assays and immunoblot.
Even though 28 % of the participants were bitten by a Borrelia-positive tick, only 7.5% (32/428) of them developed a Borrelia infection, half of them LB. All who seroconverted removed “their” ticks significantly later than those who did not. The Borrelia load in the ticks did not explain the risk of seroconversion. Regional as well as gender differences in the Borrelia seroprevalence were found. The risk of developing a Borrelia infection after a bite by a Borrelia-infected tick is small but increases with the duration of tick feeding.
Place, publisher, year, edition, pages
Elsevier, 2016. Vol. 7, no 1, 71-79 p.
Borrelia burgdorferi sensu lato; tick bite; incidence of infection; Lyme borreliosis; asymptomatic infection; bacterial load; tick-feeding.
IdentifiersURN: urn:nbn:se:liu:diva-105475DOI: 10.1016/j.ttbdis.2015.08.009ISI: 000366953400012OAI: oai:DiVA.org:liu-105475DiVA: diva2:707590
Funding agencies: Swedish Research Council Branch of Medicine [K2008-58X-14631-06-3]; Medical Research Council of South-East Sweden [FORSS-8967, FORSS-12573, FORSS-29021, FORSS-86911]; EU Interreg IV A project ScandTick ; County Council of Ostergotland [LIO-56191];2014-03-252014-03-252016-02-24Bibliographically approved