The distribution of tick-borne encephalitis virus genotypes in different types of landscapes of Eastern Siberia

To find out what is the role of some environmental factors in the formation of a heterogeneous viral population, the analysis of the distribution of tick-borne encephalitis virus (TBEV) genotypes in different types of landscapes of Eastern Siberia has been carried out. In our study, it was shown that TBEV area in all investigated landscapes of Eastern Siberia is represented not only by TBEV of genotype 3, absolute dominance of which is noted in the studied regions, regardless the landscapes where the foci are located, but also by strains of other genotypes. The relationship between genotypes 1,3 and "polytypic" strains with a certain type of landscape and the degree of their development by man has not been established. The prevailing number of strains of TBEV genotype 5 is isolated from the material collected in the Transbaikalia, in the landscapes of the mountain taiga. They, as well as the strain of genotype 4, are found in the foci, where joint circulation of several TBEV genotypes is noted. The strains of TBEV genotype 2 were revealed in the landscapes of plains and plateaus taiga and insular steppes and forest steppes of the southern part of the Baikal region. Moreover, the detection of RNA of TBEV genotype 2 in the "polytipic" 763-87 and 765-87 strains isolated in the floodplain and forest-steppe landscapes of the Barguzin hollow does not exclude the possibility of circulation of TBEV genotype 2 in the Transbaikalian foci. The greatest genetic heterogeneity of TBEV is observed in natural foci located along Lake Baikal and in the southeastern part of Transbaikalia.

tick-borne encephalitis virus, genotype, landscape type, Eastern Siberia

1. Верхозина М.М., Злобин В.И., Козлова И.В., Демина Т.В., Джиоев Ю.П., Беликов С.И., Борисов В.А., Данчинова Г.А., Арбатская Е.В., Лисак О.В., Дорощенко Е.К., Протасова Е.Г. Эколого-генетический анализ популяции вируса клещевого энцефалита в Восточной Сибири // Бюл. ВСНЦ СО РАМН. - 2007. - № 4. - С. 53-59

2. Верхозина М.М., Козлова И.В., Демина Т.В., Джиоев Ю.П., Дорощенко Е.К., Лисак О.В., Карань Л.С., Ткачев С.Е., Злобин В.И. Молекулярно-эпидемиологическая и эколого-географическая характеристика вируса клещевого энцефалита в Восточной Сибири // Инфекции, передаваемые клещами в Сибирском регионе. - 2011. - С. 84-108

3. Демина Т.В., Джиоев Ю.П., Козлова И.В., Верхозина М.М., Ткачев С.Е., Дорощенко Е.К., Лисак О.В., Парамонов А.И., Злобин В.И.. Генотипы 4 и 5 вируса клещевого энцефалита: особенности структуры геномов и возможный сценарий их формирования // Вопросы вирусологии. - 2012. - № 4. - С. 12-19

4. Злобин В.И., Борисов В.А., Верхозина М.М., Малов И.В., Холмогорова Г.Н.. Клещевой энцефалит в Восточной Сибири. - Иркутск: РИО ВСНЦ СО РАМН, 2002. - 182 с

5. Козлова И.В., Верхозина М.М., Демина Т.В., Джиоев Ю.П., Ткачев С.Е., Карань Л.С., Дорощенко Е.К., Лисак О.В., Сунцова О.В., Парамонов А.И., Черноиванова О.О., Ревизор А.О., Злобин В.И. Генетические и биологические свойства оригинальной группы штаммов вируса клещевого энцефалита, циркулирующей в Восточной Сибири // Эпидемиология и вакцинопрофилактика. - 2012. - № 64. - С. 14-25

6. Львов Д.К., Ильичев В.Д. Миграция птиц и перенос возбудителей инфекций. - М.: Наука, 1979. - 270 с

7. Dudley J., Nei M., Kumar S. (2007). MEGA 4: Molecular Evolutionary Genetics Analysis (MEGA) software version 4.0. Mol Biol Evol, 24, 1596-1599.

8. Hayasaka D., Suzuki Y., Kariva H. (1999). Phylogenetic and virulence analysis of tick-borne encephalitis viruses from Japan and far-eastern Russia. J Gen Virol, 80 (12), 3127-3135.

9. Hoogstraal H., Kaiser M.N., Traylor M.A. (1963). Ticks (Ixodidae) on birds migrating from Europe and Asia to Africa 1956-1961. Bull World Health Organ, 28, 235-262.

10. Waldenstrum J., Lundkvist A., Falk K.I. (2007). Migrating birds and tick-borne encephalitis viruses. Emerg Infect Dis, 13 (8), 1215-1218.