Genome analysis of influenza A virus strains isolated during an epidemic of 1979-1980

Abstract

The genome and polypeptides of influenza A virus H3N2 strains isolated during the epidemic of 1979-1980 in the U.S.S.R. and G.D.R. have been analysed. Five varieties of H3N2 strains differing in a number of genes have been found. The isolates of the first group were similar to the A/Texas/l/77 strain in all the genes; the isolates of the second group were similar to the A/Bangkok/I/79 strain in all the genes; the strain representative of the third variety, contained all the genes except gene 4 close to those of the A/Bangkok/I/79 strain; the isolates of the fourth group contained genes 7 and 8 similar to those of the A/Bangkok/I/79 strain while the other genes corresponded to those of no strains under comparison; the viruses of the fifth group contained gene 3 similar to that of A/Moscow/406/76 strain, gene 7 was similar to that of A/Texas/I/77 strain and the other genes differed from all other strains compared. The data obtained indicate that during an influenza epidemic occurring in a certain region several influenza virus varieties of the same serotype can circulate simultaneously, differing not only in the antigenic specificity of the haemagglutinin, but also in other genes