Division of Zoonoses, Institute of Special Economic Animal and Plant Sciences, Chinese Academy of Agricultural Sciences CAAS, 15 Luming Street, Jilin 132109, China.
Vet Microbiol. 2010 Jan 6;140(1-2):34-42. doi: 10.1016/j.vetmic.2009.07.010. Epub 2009 Jul 10.
Canine distemper virus (CDV) infects a variety of carnivores, including wild and domestic Canidae. Genetic/antigenic heterogeneity has been observed among the various CDV strains, notably in the haemagglutinin (H) gene, that appears as a good target to gather epidemiological information. Based on sequence analysis of the H gene, wild-type CDV strains cluster into distinct geographic lineages (genotypes), irrespective of the species of isolation. The sequence of the H gene of 28 CDV strains detected from both vaccinated and non-vaccinated breeding foxes, raccoon dogs and minks from different geographical areas of China during the years 2004-2008 was determined. All the CDV strains but two (strains HL and HLJ2) were characterized as Asia-1 genotype and were highly similar to each other (96.2-99.7% at the amino acid [aa] level) and to other Asia-1 strains (96.1-99.5% aa) previously detected in China. The CDV strains HL and HLJ2 were both collected from foxes in Heilongjiang province in 2005. Strain HL resembled CDVs of the Arctic genotype (GR88-like) and displayed high aa identity (98.0%) to the Chinese canine strain Liu. By converse, strain HLJ2 was barely related to CDVs of the Asia-2 genotype (88.7-90.3% aa identity), and could represent a novel CDV genotype, tentatively proposed as Asia-3. These results suggest that at least three different CDV genotypes, distantly related (81.8-91.6% aa identity) to the vaccine strains, Onderstepoort-like (America-1 genotype), are currently circulating in breeding foxes, raccoon dogs and minks in China, and that the genotype Asia-1 is predominant. Whether the diversity between wild-type CDVs and the vaccine strains may affect, to some extent, the efficacy of the vaccines deserves further investigations.
犬瘟热病毒（CDV）感染多种食肉动物，包括野生和家养的犬科动物。不同的 CDV 株之间存在遗传/抗原异质性，尤其是在血凝素（H）基因中，这是收集流行病学信息的一个很好的目标。基于 H 基因的序列分析，野生型 CDV 株分为不同的地理谱系（基因型），而与分离的物种无关。2004-2008 年期间，从中国不同地理区域的接种和未接种繁殖狐、貉和水貂中检测到的 28 株 CDV 株的 H 基因序列被确定。除了 2 株（HL 和 HLJ2 株）外，所有 CDV 株都被特征化为亚洲-1 基因型，彼此之间非常相似（氨基酸[aa]水平为 96.2-99.7%），与之前在中国检测到的其他亚洲-1 株（96.1-99.5% aa）也非常相似。HL 和 HLJ2 株均于 2005 年从黑龙江省的狐狸中分离得到。HL 株类似于北极基因型（GR88 样）的 CDV，与中国犬株 Liu 的 aa 同一性高达 98.0%。相反，HLJ2 株与亚洲-2 基因型的 CDV 几乎没有关系（aa 同一性为 88.7-90.3%），可能代表一种新的 CDV 基因型，暂提议为亚洲-3。这些结果表明，在中国的繁殖狐、貉和水貂中，至少有三种不同的 CDV 基因型（与疫苗株的 aa 同一性为 81.8-91.6%）在传播，这些基因型与疫苗株的关系较远，分别为奥登堡样（美洲-1 基因型）、 Onderstepoort 样（美洲-1 基因型）和 Asia-1 基因型。野生型 CDV 与疫苗株之间的多样性是否会在一定程度上影响疫苗的效力，值得进一步研究。
