[Longitudinal observations on the circulation of rotaviruses in Nizhny Novgorod using molecular-genetic methods]

1370 natural strains of human rotaviruses which circulated on the territory of Nizhny Novgorod during the period of 1984-1996 were differentiated with the use of electrophoretic typing of RNA. 58 electrophoretic types of RNA were detected; of these, 8 types dominated in the populations. The specific features of the circulation of strains with different electrophoretic types of RNA were characterized: co-circulation, time of domination, the change of the dominating genetic variant of the virus consecutively between seasons and during seasons. The change of domination during seasons, connected with the specific features of the circulation of rotaviruses having RNA of electrophoretic type 3, determined the winter-spring dynamics of the monthly detection rate of rotaviruses and was accompanied by an rise in the level of their detection. Such change was supposedly be caused by the biological properties of rotavirus with RNA of electrophoretic type 3, virulence constituting one of these properties. The study revealed that a change in the domination of the electrophoretic type of rotavirus, reflecting the change of the antigenic variant between seasons, occurred gradually during 5 seasons of the active circulation of strains.