Genome Analysis of Influenza A Virus Strains Isolated During an Epidemic of 1979-1980

Abstract

The genome and polypeptides of influenza virus H3N2 strains isolated during the epidemic of 1979-1980 in the USSR and East Germany were analyzed. Five varieties of H3N2 strains differing in a number of genes were found. The isolates of the 1st group were similar to the A/Texas/1/77 strain in all genes; the isolates of the 2nd group were similar to the A/Bangkok/1/79 strain in all genes; the strain representative of the 3rd variety contained all genes except gene 4 close to those of the A/Bangkok/1/79 strain; the isolates of the 4th group contained genes 7 and 8 similar to those of the A/Bangkok/1/79 strain while the other genes corresponded to those of no strains under comparison; the viruses of the 5th group contained gene 3 similar to that of A/Moscow/406/76 strain, gene 7 was similar to that of A/Texas/1/77 strain and the other genes differed from all other stains compared. 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 hemagglutinin, but also in other genes.