BORRELIAE IN IMMATURE IXODES-RICINUS (ACARI, IXODIDAE) TICKS PARASITIZING BIRDS IN THE CZECH-REPUBLIC

Of 411 forest birds of 33 species examined near Valtice, Czech Republi c, 29% were infested with Ixodes ricinus (L.): 2.2% were parasitized b y Haemaphysalis concinna Koch. Borreliae were detected in 5.1 and 11.7 % of larval and nymphal I, ricinus, respectively. None of the 13 H. co ncinna tested was infected. In total, 3.2% of the birds examined were parasitized by I. ricinus immatures infected by borreliae. Borreliae-c ontaining ticks parasitized European robin, Erithacus rubecula (L.); E urasian blackbird, Turdus merula L.; Blackcap, Sylvia atricapilla (L.) ; Eurasian chiffchaff, Phylloscopus collybita (Vieillot); Great tit, P arus major L.; and Eurasian jay, Garrulus glandarius (L.). The isolate BR-34 from a nymphal I. ricinus off a Eurasian blackbird had a sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein pattern, r eactions to monoclonal antibodies, and fragments of HindIII digested D NA probed with fla and ospA genes that suggested to us that it belongs to the genospecies Borrelia garinii. Free-living birds may be involve d in the circulation of B. burgdorferi sensulato principally as dissem inators of infected ixodid ticks to new areas.