Submitted to: International Symposium on Avian Influenza
Publication Type: Abstract Only
Publication Acceptance Date: 2/1/2015
Publication Date: N/A
Technical Abstract: In the poultry industry, live virus vaccines are used to induce immunity against numerous respiratory pathogens. These are typically lower virulent forms of virus which are limited in replication and pathology, but induce mucosal, humoral, and cellular immunity. Because of the potential for reversion to virulence and trade restrictions, low pathogenic (LP) forms of avian influenza (AI) are not considered as suitable vaccine candidates for commercial use in the field. However, because most LPAI infections of poultry are transient in nature, resulting in little to no clinical disease, the question of immunity induced following LP infection was addressed. In these studies, specific pathogen free (SPF) chickens were inoculated with H7 LPAI of either chicken, turkey, or duck origin and later challenged against the 2012 H7N3 highly pathogenic AI from Mexico. Results demonstrate variable levels of protection ranging from 100% to 40%. As expected, poultry adapted viruses induced higher immunity than the duck isolate. Taken together, these studies indicate that unlike other respiratory viruses, LPAI infection is not sufficient to protect against HPAI. Results of immune responses to individual isolates will be discussed.