Influenza viruses isolated from waterfowl in southern Ontario, 1976-1978

From 1976 to 1978, samples were collected from 720 ducks, 100 terns, and 50 gulls for attempted isolation of influenza viruses. Influenza viruses were isolated from 32 of the ducks samples: 10.2% of those sampled in 1976, 4.8% in 1977, and 2.4% in 1978. At least six different hemagglutination and seven neuraminidases were identified in the viruses isolated, in 14 different combinations.