Submitted to: Western Poultry Disease Conference
Publication Type: Proceedings
Publication Acceptance Date: 1/1/2003
Publication Date: 3/1/2003
Citation: Tumpey, T., Swayne, D.E. 2003. Protective Efficacy of an Inactivated Avian Influenza Vaccine Against Challenge With A 2002 H7N2 Avian Influenza Isolate. Western Poultry Disease Conference Proceedings, CD-Rom, 2003. Interpretive Summary: Interpretive summary not required.
Technical Abstract: The outbreak of H7N2 low pathogenicity avian influenza (LPAI) in Virginia this past year raised questions about the potential of available vaccines to provide protection. The current study was undertaken to determine if an existing commercial H7N2 avian influenza vaccine could provide protection against a recent LPAI (H7N2) isolate. Low pathogenic A/Chicken/Pennslyvania/21342/97 was used as the vaccine strain and emulsified in a proprietary oil-based vaccine (Lohmann Animal Health, Waterville ME). Groups of 10 1-day-old and 3-wk-old turkeys (British United Turkeys of America, Lewisburg, WV) were immunized subcutaneously with either the inactivated vaccine or normal allantoic fluid emulsified in the same adjuvant. In vaccine trials, neither sham-vaccinated nor H7N2-vaccinated turkeys developed clinical signs or death following challenge with A/Turkey/Virginia/158512/02 (H7N2) LPAI virus. However, high titers of challenge virus could be detected from swabs collected from the oropharynx on days 1-7 after challenge in the sham-vaccinated group. Low or undetectable viral titers were recovered from cloacal samples from the sham-vaccinated birds. The inactivated vaccine groups (1x and 2x vaccinated) had a significant reduction in titers of challenge virus shed from the oropharynx when compared to sham-vaccinated groups for days 1-7 after challenge. These studies suggest that a currently available commercial H7N2 avian influenza vaccine can provide protection against a recent H7N2 avian influenza isolate.