Infectious anaemia in chickens is an immunosuppressive disease of domestic fowl caused by Gyrovirus. The disease tends to be subclinical and is characterised by growth retardation in chickens, haemorrhages in the subcutaneous tissue and muscle. Increased mortality occurs only in chicks up to 2-3 weeks of age. Blood counts show anaemia and leucocytopenia.
Mortality is low, the main problem being increased susceptibility to secondary infections due to anaemia and immunosuppression.