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Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 12/16/2013 Publication Date: 1/27/2014 Citation: Kapczynski, D.R. 2014. Evaluation of homologous inactivated influenza vaccine for protection of chickens against the H7N9 virus isolated in Anhui, China during 2013 [abstract]. Southern Conference on Avian Diseases, January 27-28,2014, Atlanta, Georgia. CDROM. p.31. Interpretive Summary: Technical Abstract: The recent outbreak of avian influenza (AI) H7N9 in humans in China in 2013 has resulted in approximately 30 % mortality. The genetic composition of these H7N9 viruses appears to be solely of avian origin. Although few isolations of these viruses have been demonstrated on poultry farms, the correlation between live bird market shut downs and reduced human infections in China underscores a linkage between poultry and humans. In response to the outbreak, vaccine efficacy trials were recently performed to determine if inactivated H7N9 vaccine could increase resistance of birds to clinical disease and shedding of virus. A homologous A/H7N9 vaccine was formulated into an inactivated emulsion and injected at various doses into 3 week old SPF birds. Birds were challenged at 6 weeks of age with 108 EID50 per bird delivered via intranasal route. Results demonstrate that at the highest dose, 512 HA units, demonstrated 100 % protection. In contrast, birds receiving less antigen or sham vaccination demonstrated 10 % mortality. All vaccine groups demonstrated improved weight gain compared to sham vaccinated birds. Taken together, these results indicate that the homologous vaccine can provide protection to poultry against this recent H7N9 virus. |
