Infectious bursal disease

Infectious bursal disease is a contagious viral disease of young chickens caused by infectious bursal disease virus. It damages the bursa of Fabricius, disrupting B-cell development and potentially suppressing immune function.

Connect

Infectious bursal disease virus: A birnavirus that causes infectious bursal disease in chickens. Its replication in developing B cells drives the characteristic bursal injury.
Infectious bursal disease vaccination: The use of vaccines to protect chickens against infectious bursal disease. Vaccination is a central control measure, but maternal antibodies and vaccine strength affect timing and safety.
Very virulent infectious bursal disease virus: A highly pathogenic variant of infectious bursal disease virus associated with severe flock outbreaks. It can cause high mortality and marked bursal damage compared with classical strains.
Secondary infection: An infection that develops when another disease or condition weakens host defenses. Immune suppression after bursal damage can leave chickens more vulnerable to other pathogens.
Bursa of Fabricius: A lymphoid organ in birds where B lymphocytes mature. The virus targets this organ, making its damage the disease’s defining lesion.
Infectious bursal disease diagnosis: Identification of infectious bursal disease using clinical, pathological, and laboratory evidence. Clinical signs alone cannot reliably distinguish this disease from other causes of flock illness.
Variant infectious bursal disease virus: A group of antigenically distinct infectious bursal disease viruses that can evade some vaccine-induced protection. Variant viruses may damage the bursa and undermine protection without the classic severe clinical picture.
Vaccine response: The immune reaction produced after vaccination, including antibody and cellular responses. B-cell depletion can reduce the strength or reliability of responses to unrelated vaccines.
B lymphocyte: An adaptive immune cell that develops into antibody-producing cells or memory cells. Infectious bursal disease virus preferentially damages immature B lymphocytes.
Infectious bursal disease virus genotyping: Classification of infectious bursal disease virus isolates using genetic sequence data. Genotyping helps track circulating strains and interpret vaccine-related detections.