Chicken anaemia virus

Chicken anaemia virus, or CAV, is a member of the circoviridae family. It is a non-enveloped icosahedral single stranded DNA virus.

Infection causes anaemia, bone marrow atrophy, and severe immunosuppression in poultry as the virus affects the production of red blood cells (RBC), white blood cells (WBC) and platelets. Clinical signs of CAV infection are predominantly found in young chicks due to vertical transmission from the breeder hens whose maternal antibodies have not yet formed following exposure. Clinical disease is rare today because of the widespread practice of vaccinating breeders, but the subclinical form of the disease - which normally affects birds more than two weeks of age following horizontal transmission of the virus via the oro-faecal route - is ubiquitous. Additionally, the virus is very resistant in the environment, making elimination very difficult. It is not a zoonosis. The vaccine has the ATCvet code QI01AD04