ABSTRACT
This chapter focuses on vaccine development to prevent disease and death from LPAIV and HPAIV in poultry and to eliminate HPAIV from meat and eggs. During vaccination against avian influenza virus (AIV), the potential exists for vaccinated animals to acquire AIV infection, which may go unnoticed, due to the lack of clinical signs as a consequence of vaccine protection. Inactivated vaccines are inexpensive and highly effective, although multiple doses may be needed for life-long protection in long lived birds, such as table-egg layers and breeders. Vectored vaccines are the second most commonly utilized vaccines against AIV, accounting for approximately 4.5% of vaccines used. For AI vaccines, only inactivated whole-virus vaccines and virus-like particle vaccines require the use of adjuvants because they are not able to replicate, and thus cannot stimulate the immune response sufficiently by themselves. Inactivated whole-virus AIV vaccines are by far the most widely applied worldwide, accounting for about 95% of all vaccines used.
