Author
Pantin Jackwood, Mary | |
Swayne, David | |
Suarez, David |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 10/6/2014 Publication Date: 10/20/2014 Citation: Pantin Jackwood, M.J., Swayne, D.E., Suarez, D.L. 2014. Vaccination of domestic ducks against H5N1 HPAI [abstract]. 10th Asia Pacific Poultry Conference,October 20-23, 2014, Jeju, South Korea. Flash drive. Interpretive Summary: Technical Abstract: Domestic ducks play an important role in the epidemiology of H5N1 and H5N8 highly pathogenic avian influenza (HPAI) viruses, and therefore, successful control of HPAI in ducks is vital for the eradication of the disease in poultry. Vaccination can be used as a tool for supporting eradication by increasing the resistance of ducks to field challenge and by reducing the amount and duration of virus shed in the environment. Results from field and laboratory evaluation of vaccines against H5N1 HPAI in ducks indicates that factors such as challenge virus, duck species and use, vaccination protocols, and proper use of vaccines may significantly influence the outcome of the vaccination program. Other factors, including the role of maternally derived antibodies and co-infection with other pathogens, remain to be determined in ducks. Domestic ducks include different species and breeds, and the susceptibility to infection, disease and response to vaccination varies depending on the species and age of the bird. Current vaccines and vaccination practices are insufficient for the control of HPAI virus infections in domestic waterfowl and new vaccination strategies are needed. Although vaccination has proven effective in protecting ducks against disease, shedding of the virus still occurs in clinically healthy vaccinated populations. Vaccine failure might occur due to several reasons, including low antigenic homology between the vaccine and the circulating strain, an insufficient viral antigen load in the vaccine, the use of an adjuvant not adapted for ducks, and/or not providing appropriate booster vaccinations. When assessing vaccine efficacy in field settings, strategies that account for differences between duck species may need to be implemented. Better matching of vaccines with circulating viruses, optimized vaccines, and vaccination programs should improve the results of influenza immunization in ducks. To effectively control the virus from circulating in poultry, an efficient post-vaccination surveillance program should also be established. A control program should include strict quarantine, movement controls on animals and equipment, increased biosecurity, extensive surveillance, depopulation of infected animals, and a comprehensive education program for the public. |