Several commercial live attenuated vaccines are now available. The vaccines stimulate both local and systemic immunity, some even in the presence of maternal immunity.
Although it is well known that different subtypes exist, studies have shown that in general there is good cross protection between the subtypes. Live attenuated subtype A or subtype B vaccines (chicken or turkey origin) protect against challenge with subtypes A, B or C. Live cell culture attenuated vaccines and inactivated vaccines are currently being used in Europe and other parts of the world to control disease caused by subtypes A and B. Protection provided by type C against challenge with types A or B is less solid.

Vaccine applied with spray to day old chicks in the hatchery