Epidemiology of tick-borne encephalitis in Latvian SSR
Babenko, L.V.; Prisiagina, L.A.; Smirnov, O.V.; Shenigson, B.S.; Nesaule, V.M.
Meditsinskaia Parazitologiia i Parazitarnye Bolezni 44(5): 533-541
1975
ISSN/ISBN: 0025-8326 PMID: 1219350 Document Number: 82970
Ecological and epidemiological investigations on tick-borne encephalitis in the Latvian SSR [USSR] were concentrated in the Riga area. The incidence of tick-borne encephalitis in the entire republic was analyzed. In disease foci selective serological surveys were carried out twice, and the ecology of vectors, their abundance, the virus carrier state, and animal reservoirs [common red-backed vole] studied. The relationship between tick distribution and types of forests was established. Recently most patients were recognized in the city of Riga and the Riga district. Riga residents with tick-borne encephalitis generally were not associated with forest by their occupation. Infection was contracted during recreational visits to forests, during mushroom and berry collections, etc. Differences in seasonal incidence in districts with different vectors were observed. In central and western areas where the vector was Ixodes ricinus the incidence peak was in Aug.-Sept., and in eastern areas (vector I. persulcatus) in June. Recommendations for protection of different population groups against tick-borne encephalitis are presented.