Jeon Woo-Jin, Choi Kang-Seuk, Lee Dong-Woo, Lee Eun-Kyoung, Cha Sang-Ho, Cho Sun-Hee, Kwon Jun-Hun, Yoon Yeo-sung, Kim Sun-Joong, Kim Jae-Hong, Kwon Hyuk-Joon
Avian Disease Division, National Veterinary Research and Quarantine Service, Gyeonggi-Do, Korea.
Virus Genes. 2009 Dec;39(3):342-51. doi: 10.1007/s11262-009-0394-6. Epub 2009 Sep 1.
We conducted a molecular epizootiological study of infectious bursal disease (IBD) in Korea by analyzing 85 IBD viruses (IBDVs) obtained from vaccinated or unvaccinated flocks between 1980 and 2007. Phylogenetic analysis of the partial nucleotide sequence of the hypervariable region of the VP2 gene (nucleotides 661-1020) and pathogenicity tests revealed more genetic and phenotypic diversity of IBDV in Korea than has been reported previously. We showed that very virulent IBDVs (vvIBDVs) were already present in Korea in 1986. Moreover, vvIBDVs were repeatedly detected in Korean poultry that had been vaccinated, which casts doubt on the IBD vaccine programs. We also identified novel putative antigenic variant (AV)-like IBDV isolates on the basis of their antigenic indices and the presence of amino acid changes (P222S or P222T-A321D) that are known to affect the antigenicity of VP2. These observations suggest that future studies examining the efficacy of conventional vaccines against atrophy of the bursa of Fabricius and vvIBDV shedding may be useful. Moreover, it will be of interest to determine the prevalence of putative Korean antigenic variants and whether these strains exert immunosuppressive effects in vaccinated birds.
我们通过分析1980年至2007年间从接种或未接种疫苗的鸡群中获得的85株传染性法氏囊病病毒（IBDV），对韩国的传染性法氏囊病（IBD）进行了分子流行病学研究。对VP2基因高变区部分核苷酸序列（核苷酸661 - 1020）的系统发育分析和致病性测试表明，韩国IBDV的遗传和表型多样性比以前报道的更多。我们发现，1986年韩国就已存在超强毒IBDV（vvIBDV）。此外，在接种过疫苗的韩国家禽中反复检测到vvIBDV，这对IBD疫苗计划提出了质疑。我们还根据其抗原指数以及已知会影响VP2抗原性的氨基酸变化（P222S或P222T - A321D），鉴定出了新型的假定抗原变异（AV）样IBDV分离株。这些观察结果表明，未来研究传统疫苗对法氏囊萎缩和vvIBDV排毒的效果可能会有所帮助。此外，确定韩国假定抗原变异株的流行情况以及这些毒株是否对接种疫苗的禽类产生免疫抑制作用将很有意义。
