Chicken anemia viruses (CAVs) are small, non-enveloped viruses that belong to the family Circoviridae. These viruses primarily infect chickens, causing a highly contagious and widespread disease known as chicken infectious anemia (CIA) or chicken anemia.
The disease caused by CAVs is characterized by a reduction in the number of red blood cells in infected chickens, resulting in anemia and immunosuppression. The virus targets the bone marrow, where it replicates in the rapidly dividing cells, leading to the destruction of the developing erythroblasts and lymphocytes.
In addition to anemia, CAV infection can lead to a variety of clinical signs such as pale combs and wattles, lethargy, poor growth, and increased susceptibility to secondary infections. Mortality rates can vary, with young chicks being particularly susceptible to severe disease.
CAV transmission occurs both horizontally and vertically. Horizontal transmission happens through direct contact with infected birds, contaminated feces, or contaminated fomites, while vertical transmission occurs when the virus is transmitted from the infected hen to the developing embryo in the egg.
Prevention and control of CAV infections involve good biosecurity practices, including strict hygiene measures, disinfection protocols, and preventing contact between infected and healthy chickens. Vaccination is also an effective control measure, with attenuated or inactivated vaccines available for use.
Overall, chicken anemia viruses are significant pathogens in the poultry industry, causing economic losses through reduced productivity and increased mortality. Timely detection, prevention, and control measures are essential for managing this viral disease effectively.
