Genospecies ofBorrelia BurgdorferiS. L. inIxodes RicinusTicks in Lithuania

The tick Ixodes ricinus, the most important vector of Lyme disease caused by Borrelia burgdorferi, has spread throughout the territory of Lithuania. The Lyme disease is the most frequently reported vector-borne zoonosis in this country. The aim of the study was to estimate the density of I. ricinus and the prevalence of B. burgdorferi sensu lato in I. ricinus in Lithuania as well as to determine the bacterial genospecies. Two-hundred and four ticks were collected in eight districts of Lithuania and tested individually for Borrelia genospecies using polymerase chain reaction (PCR) techniques to identify both B. burgdorferi s. l. and its genospecies (Borrelia garinii, B. afzelii, B. burgdorferi sensu stricto). Prevalence of Borrelia infection in adult ticks fluctuated between 5% and 35% in different districts of Lithuania. Borrelia afzelii (9.3%) dominated over B. garinii (2.5%). Infection of I. ricinus with B. afzelii was recorded for the first time in Lithuania.