Isolation of influenza A viruses from birds in Great Britain during 1980 and 1981

During 1980 and 1981 influenza A viruses of subtypes H3N2, H3N8, H4N1, H4N6, H6N2, H6N8, H7N7, H11N8 and H11N9 were isolated from birds in Great Britain, usually as a result of investigations of disease or death. However, all viruses were shown to be of low virulence for chickens in pathogenicity index tests. There was one occurrence of influenza virus infection of turkeys (H6N8) but viruses were frequently obtained from domestic ducks. Other viruses were isolated from exotic birds in zoos or bird collections.