In countries where highly pathogenic MDV occurs, parents should be vaccinated with Rispen's strain, allowing commercial progeny to be immunized using the less expensive HVT strain alone or in combination with the potentiating SB1 strain. Cell-associated, frozen vaccines require special storage in a liquid nitrogen canister. Careful reconstitution using the diluents supplied by the vaccine manufacturer is necessary to maintain viability of the vaccine virus. To allow vaccinated flocks to develop immunity, it is essential to place day old chicks in houses which have been thoroughly decontaminated. Pathogenic Delaware variants A through E predominate in the USA and Central America.
Turkey strains are apathogenic to chickens.
The disease affects immature chickens world wide. The variants are more immunosuppressive than the classic strains. Avibirnaviruses are immunosuppressive and predispose flocks to intercurrent viral pathogens and secondary bacterial infection. Infectious Bursal Disease is a major restraint to productivity and profitability in the poultry industries of both industrialized and developing nations. Indirect infection with IBDV occurs as the agent can survive in the environment for up to 3 months.