Acute infectious bursal disease in poultry: A review

TLDR: This review is focused on the acute form of infectious bursal disease (IBD) caused by very virulent IBD virus (vvIBDV), and recombinant vaccines and virus-neutralizing factor technology might have an advantage over other approaches.

Abstract: This review is focused on the acute form of infectious bursal disease (IBD) caused by very virulent IBD virus (vvIBDV). First described in Europe about 10 years ago, this new form of the disease has rapidly spread all over the world, causing dramatic losses; after a decade, it still represents a considerable threat to the poultry industry. Emergence of the acute forms of the disease has drastically changed the epidemiology of IBD. Although their origin is still under investigation, vvIBDVs have spread all over the world in a very explosive but conserved manner. This raises the question of the origin of vvIBDVs, of the possible existence of reservoirs and of the possible emergence of new, distinct lineages in the future. While it has become clear that amino acids within the variable region of virus protein VP2 account for the molecular basis of antigenic variation, no definite hot spot that determines pathogenicity has been identified. Fingerprints of VP2 on vvIBDVs have to be considered more as common evo...