Tick-borne encephalitis virus infections in Lithuanian domestic animals and ticks

In order to obtain information about the distribution of tick-borne encephalitis virus (TBEV) in Lithuania, sera of domestic animals were screened for TBEV antibodies by haemagglutination inhibition test. Samples were collected in 2001 from 423 cows, 561 goats and 118 sheep during a prophylactic examination or vaccination by a local veterinary specialist. In addition, a total of 3234 Ixodes ricinus ticks in 436 pools were collected and tested by RT-PCR for the presence of TBEV RNA (detailed analysis with genetic characterization is published separately [Han et al, J Med Virol 2005 (in press)]). Domestic animal sera from 8/18 districts were positive with an overall seropositivity of 1.7% with considerable regional differences. Sheep from the Radviliskis region had the highest seropositivity rate (16%). In comparison, the proportion of tick pools positive for TBEV-RNA was 1.38%, ranging from 1.03% in Panavezys, 3.33% in Siauliai to 16% in Radviliskis.