Occurrence of Borrelia burgdorferi sensu stricto, Borrelia garinii and Borrelia afzelii in the Ixodes ricinus ticks from Eastern Slovakia.

A total of 2816 unfed adults nymphs of Ixodes ricinus ticks were collected from vegetation in Kosice (Eastern Slovakia) from 1994 to 1997. Prevalence of Borrelia burgdorferi s. l. in I. ricinus ticks, detected by dark field microscopy, varied and depended upon the year and the habitat of the collected ticks. The lowest prevalence was observed in 1994 (4.8%). During 1995 it increased to 17.2% and during the next two years decreased to 15.5% and 14.2%. The rate of infection varied from 2.1 to 23.3% within 10 examined habitats of the Kosice area. A different value of relative density of ticks was observed in various habitats. It ranged from 9-212 ticks per collecting hour within one flagged area (600 m2) which is 1.5-35.5 ticks per 100 m2. Eight isolates were obtained from the infected ticks. Electrophoresis and immunoblotting with 6 monoclonal antibodies were used for the identification of Borrelia strains. Three tick isolates were identified as B. burgdorferi s. s. and the other three isolates were found to be B. garinii. One strain reacted as a mixed culture of B. burgdorferi s. s., and B. garinii. The strain originated from the Vihorlat Mountains habitat and was detected by PCR-SSCP as B. burgdorferi s. s. with a small amount of B. afzelii. The obtained results emphasize the epidemiological importance not only of B. garinii and B. afzelii but also of B. burgdorferi s. s. in Central Europe.