tailieunhanh - Báo cáo khoa học: "An inactivated vaccine to control the current H9N2 low pathogenic avian influenza in Korea"

Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: An inactivated vaccine to control the current H9N2 low pathogenic avian influenza in Korea | J. Vet. Sci. 2008 9 1 67-74 JOURNAL OF Veterinary Science An inactivated vaccine to control the current H9N2 low pathogenic avian influenza in Korea Jun Gu Choi1 Youn Jeong Lee1 Yong Joo Kim1 Eun Kyoung Lee1 Ok Mi Jeong1 Haan Woo Sung2 Jae Hong Kim3 Jun Hun Kwon1 National Veterinary Research and Quarantine Service Anyang 430-824 Korea 2Department of Veterinary Medicine Kangwon National University Chunchon 200-701 Korea 3Laboratory of Avian Diseases College of Veterinary Medicine Seoul National University Seoul 151-742 Korea The H9N2 subtype low pathogenic avian influenza is one of the most prevalent avian diseases worldwide and was first documented in 1996 in Korea. This disease caused serious economic loss in Korea s poultry industry. In order to develop an oil-based inactivated vaccine a virus that had been isolated in 2001 A chicken Korea 01310 2001 was selected based on its pathogenic antigenic and genetic properties. However in animal experiments the efficacy of the vaccine was found to be very low without concentration of the antigen 27 to 210 hemagglutinin unit . In order to overcome the low productivity we passaged the vaccine candidate virus to chicken eggs. After the 20th passage the virus was approximately ten times more productive compared with the parent virus. For the most part the passaged virus maintained the hemagglutinin cleavage site amino acid motif PATSGR GLF and had only three amino acid changes T133N V216G E439D H3 numbering in the hemagglutinin molecule as well as 18 amino acid deletions 55-72 and one amino acid change E54D in the NA stalk region. The amino acid changes did not significantly affect the antigenicity of the vaccine virus when tested by hemagglutination inhibition assay. Though not complete the vaccine produced after the 20th passage of the virus 01310 CE20 showed good protection against a homologous and recent Korean isolate A chicken Korea Q30 2004 in specific pathogen- free chickens. The vaccine developed in this study would