Vector-borne Infectious Diseases in Climate Change Investigations (VICCI):

Project 1: Prospective Study on the Presence of Borrelia burgdorferi s.l. species in Ixodes ricinus in Bavaria

Project Director

Dr. Christiane Klier, Dr. Volker Fingerle and PD Dr. Dr. Andreas Sing
Section Infectiology, National Reference Centre for Borreliae, Bavarian Health and Food Safety Authority, Oberschleißheim


Over the past years there is growing awareness among health professionals as well as the public in respect to ticks and tick-borne diseases such as Lyme borreliosis (LB) or tick-borne encephalitis.

Thereof LB is the most abundant tick-borne disease caused by at least 5 different Borrelia species ascribed to the Borrelia burgdorferi (Bb) s.l. complex. Hard ticks of the Ixodes ricinus/I. persulcatus complex serve as vectors in the complex transmission cycle in nature; in Europe Bb is transmitted to humans mainly by Ixodes ricinus (IR). LB is a multisystemic disease affecting primarily skin, joint, heart and the nervous system. It is thought that global warming might result in an increase of IR populations as well as spreading of IR into higher altitudes.

At present there is little data on the prevalence and dynamics of Bb in ticks in Bavaria. In the pilot study “Epidemiological aspects of tick-borne diseases in Bavaria�? conducted in 2003/2004 ( first data on the prevalence of Bb species and OspA-types in IR was collected in different Bavarian regions.

Therefore the present project will continue the pilot study focusing on collecting longitudinal data on the prevalence of Bb species in ticks from different geographic regions, this time comprising more data regarding altitude, landuse, (micro)climatic conditions, vegetation, or tick-hosts.

Tick populations will be assessed by standardized flagging the low vegetation. Bb will be detected by PCR and further specified (Bb species/ -subtypes) by employing restriction fragment length polymorphisms (RFLP) and sequencing. Tick density as well as Bb species prevalence will be linked to environmental variables. Data will be used to develop a surveillance system on ticks- and tick-borne diseases in Bavaria.