Isolation of an influenza A virus from ostriches (Struthio camelus).

An influenza A virus of the H7 N1 subtype was isolated from young ostriches which died after developing a syndrome characterized by a green discolouration of the urine, weakness and signs of respiratory distress. Mortality varied, depending on the age of the ostriches, the presence of other infectious agents and the amount of stress to which they were exposed. Using the haemagglutination inhibition test, an amnestic response was recorded in ostriches which recovered from the disease. Pathogenicity tests indicated that the isolate was of low virulence for chickens.