Submitted to: Developments in Biologicals
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 1, 2003
Publication Date: February 25, 2004
Citation: Swayne, D.E. 2004. Vaccines for List A Poultry Diseases: Emphasis on Avian Influenza. Developments in Biologicals, 114:201-212, 2003. Interpretive Summary: Not required.
Technical Abstract: Various vaccine technologies have been shown experimentally to be effective for immunization against AI virus and include conventional inactivated oil-based whole AI virus, vectored virus, subunit protein and DNA vaccines. Vaccine-induced protection is based upon antibodies produced against the surface glycoproteins, principally the hemagglutinin, but also the neuraminidase. This protection is specific only for individual subtypes of hemagglutinin (H1-15) and neuraminidase (N1-9) proteins. Avian influenza vaccines protect chickens and turkeys from clinical signs and death, and reduce respiratory and intestinal replication of a challenge virus containing homologous hemagglutinin protein. Many of the vaccines are effective if given by single injection and provide protection for greater than 20 weeks. Protection has been demonstrated against both low and high doses of challenge virus. Furthermore, subtype H5 AI vaccine has been shown to provide protection against heterologous H5 strains with 89.4% or greater hemagglutinin deduced amino acid sequence similarity and isolated over 38 years. Currently, inactivated whole AI virus vaccines and a fowl pox-vectored vaccine with AI H5 hemagglutinin gene insert are used commercially in various countries of the world. These vaccines have some disadvantages associated with the labor requirements for parenteral administration. However, an experimental recombinant Newcastle disease virus vaccine with an AI hemagglutinin gene insert shows some promise as a low cost, mass administered aerosol vaccine. A critical issue for the use of vaccines in the field is the need to differentiate vaccinated birds from birds infected with the field virus. Differentiation is necessary for outbreak surveillance and trade. The use of AI vaccines varies with individual countries and for different AI virus subtypes.