551. Update of inactivated equine influenza vaccine strain in Japan
- Author
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Koichiro Gamoh and Shigeyuki Nakamura
- Subjects
0301 basic medicine ,040301 veterinary sciences ,efficacy ,Equine influenza ,Biology ,Antibodies, Viral ,0403 veterinary science ,03 medical and health sciences ,Influenza A Virus, H3N8 Subtype ,Antigen ,Japan ,Orthomyxoviridae Infections ,Virology ,equine influenza ,Animals ,Horses ,Antigens, Viral ,Selection system ,Ovum ,General Veterinary ,Immunogenicity ,Strain (biology) ,Antibody titer ,04 agricultural and veterinary sciences ,Note ,veterinary vaccine ,030104 developmental biology ,Florida sublineage clade 2 virus ,Vaccines, Inactivated ,Influenza Vaccines ,Equine influenza vaccine ,Horse Diseases - Abstract
Japan established a vaccine selection system, in which a committee evaluates veterinary influenza vaccines to determine if the vaccine should be updated. In 2013, it was concluded that the present equine influenza vaccine strains did not have to be updated, but clade 2 (Fc2) viruses of the Florida sublineage should be included. We collected three Fc2 viruses as candidates and conducted comparative tests. Results indicated that A/equine/Carlow/2011 (H3N8) is not suitable, because of its unstable antigenic characteristics. A comparison between A/equine/Richmond/1/2007 (H3N8) (Richmond/07) and A/equine/Yokohama/aq13/2010 (H3N8) (Yokohama/10) in eggs showed that they shared equal growth properties. Immunogenicity test in mice showed that Yokohama/10 induced higher HI antibody titers than Richmond/07. Therefore, we concluded that Yokohama/10 was the most suitable strain.
- Published
- 2017