Module 3: Pathogens

All ticks collected in module 1 and 2 are be examined for pathogens by the State Department of Public Health in Stuttgart using biomolecular methods.

Borrelia burgdorferi s.l., the causative agent of Lyme disease, is transmitted in Central Europe mainly by the castor bean tick (Ixodes ricinus). Depending on the region the prevalence (percentage of infected ticks) in these ticks varys between 10% and 27%. Dermacentor ticks can also be infected with Borrelia spp., but so far there is not enough data available for Germany.

The TBE-virus is also transmitted in Germany mainly by Ixodes ricinus. The infection rates of ticks are much lower than for Borrelia and vary greatly depending on the region. In highly endemic areas prevalences were calculated up to 2%, while in other areas infection rates of between 0.1 % and 0.5% are normal. The distribution of the TBE-virus is largely confined to southern Germany, with Baden-Württemberg and Bavaria being the most affected federal states.

Rickettsia belonging to the spotted fever group are widely distributed in Germany, both in Ixodes ricinus and in Dermacentor spp. Rickettsia helvetica is primarily found in Ixodes ricinus, the prevalences are, depending on the region, between 5% and 15%. Rickettsia raoultii is often found in Dermacentor spp. with prevalences up to 39 %. Rickettsia slovaca is less common in these ticks with infection rates up to 16%.

Babesia spp. are protozoan parasites. Their veterinary importance has long been acknowledged, but they also have a growing human pathogenic potential. In Germany there are only few data on the distribution of Babesia in ticks.