Immunoglobulin G antibodies to Borrelia burgdorferi in game animals and small mammals in eastern Slovakia.

In a survey of game animals and small mammals, the sera of 185 animals were examined for the presence of immunoglobulin G antibodies to the spirochete Borrelia burgdorferi sensu lato, which causes Lyme borreliosis. These animals comprised 59 fallow deer (Dama dama), 56 mouflons (Ovis musimon) and 70 small mammals of six different species. The sera of the fallow deer and the mouflons were examined by indirect haemagglutination assay. The sera of the small mammals were examined by modified enzyme-linked immunosorbent assay, which is available in a commercial kit. The sera of the 59 fallow deer demonstrated positivity of 40.77% (titres 1:40-1:80). The 56 mouflons demonstrated seropositivity of 17.8% (1:40-1:80). The sera of the small mammals were highly positive in the yellow-necked field mouse (Apodemus flavicollis) at 42.1% (titres 1:200-1:1,600), followed by the bank vole (Clethrionomys glareolus) at 14.3% (1:400-1:800), the common vole (Microtus arvalis) at 12.5% (1:200) and the black-striped field mouse (A. agrarius) at 10.0% (1:200-1:400-800). The authors also report the rate of infestation of these small mammals by the tick Ixodes ricinus, as these mammal species are potential reservoirs for this vector. The study focuses on the relationship between the possibility of infestation by I. ricinus and the reservoir competence of the different species under study, as well as the possible spread of disease. The detected rate of seroprevalence indicates that all the investigated animals have had contact with infected ticks.

Potential foci of Lyme borreliosis in towns.

In 1997 the presence of ticks Ixodes ricinus infected with the agent of Lyme borreliosis was detected on the vegetation of Kosice urban agglomeration. The density of ticks on the vegetation of pericentral area islands of forest stands and neglected gardens was 2.4 times lower than that observed in a peripheral park forest. Only sporadical findings of ticks were reported from the industrial central part of town with remnants of uncultivated vegetation. Central parks and housing estates were actually tick-free. Borrelia-infected ticks, from 12.8 to 15% were found in the park forest and pericentral areas. The results indicate potential risks for humans and domestic animals coming in contact with borrelia-infected ticks, also in the territory of large towns.

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.