In this study, antibody responses after vaccination against equine influenza were investigated among 1,591 horses in the Republic of Korea using the hemagglutination inhibition (HI) test. Equine influenza has not occurred since 2011 and a commercial vaccine against H3N8 has been used. The equine influenza virus, A/equine/South Africa/4/03 (H3N8), was used as the antigen in the HI assay. The mean seropositive rate was 90.5% in 2019. Except for stallion whose seropositive rate was 78.5%, all seropositive rates of other horse types were over 90%. Regionally, except for Gangwon-do and Jeju-do whose seropositive rates were 89.0% and 87.1%, all seropositive rates in other provinces were over 90%. In the future, more through vaccination against equine influenza needs to be done based on this investigation result.

Abstract
서 론
재료 및 방법
    말 검사 대상
    항원의 준비
    혈구응집억제 반응 (Hemagglutination inhibition (HI) test)
결 과
    2019년 말 항체 양성율
    유형별 항체 양성율
    연령별 항체 양성율
    지역별 항체 양성율
고 찰
REFERENCES

• In-Ohk Ouh(Viral Disease Division, Animal and Plant Quarantine Agency, College of Veterinary Medicine & Animal Disease Intervention Center)
• Min Ji Kim(Viral Disease Division, Animal and Plant Quarantine Agency)
• Hyeonhae Choi(Viral Disease Division, Animal and Plant Quarantine Agency)
• Hyoung seok Yang(Veterinary Research Institute, Jeju 63344, Jeju Special Self Governing Province)
• Sang Kyu Lee(Equine Epidemic Control & Quarantine Section, Korea Racing Authority)
• Seo Young Moon(Viral Disease Division, Animal and Plant Quarantine Agency)
• Suyeong Yun(Viral Disease Division, Animal and Plant Quarantine Agency)
• Bang-hun Hyun(Viral Disease Division, Animal and Plant Quarantine Agency)
• Soo dong Cho(Viral Disease Division, Animal and Plant Quarantine Agency)
• Choi-Kyu Park(College of Veterinary Medicine & Animal Disease Intervention Center) Corresponding Author
• Yoon-Hee Lee(Viral Disease Division, Animal and Plant Quarantine Agency) Corresponding Author