Prevalence of Borrelia burgdorferi sensu lato in the selected Ixodes ricinus (Acari: Ixodidae) population in Weilburg forests, Hesse, Germany.

We studied the presence of Borrelia burgdorferi sensu lato in Ixodes ricinus ticks collected in woodland areas in the vicinity of Weilburg (Hesse, Germany). Ticks (n = 13,347) were collected in five localities in 1996 and were fixed in 70% ethanol. Out of them, 4404 specimens were analysed individually (n = 406) and in 796 pools of 2-10 specimens (n = 3998) by the polymerase chain reaction (PCR). The calculated minimal infection rate of individual and pooled ticks was 0% in larvae (n = 280), 6.9% in nymphs (n = 3600), 13.9% in males (n = 280) and 20.9% in females (n = 244). Prevalence of B. burgdorferi s. l. in I. ricinus was determined with respect to the abundance and seasonal activity of the ticks.