He Huan, Tang Cheng, Chen Xinnuo, Yue Hua, Ren Yupeng, Liu Yan, Zhang Bin
College of Life Science and Technology, Southwest University for Nationalities, No. 16, South 4th Section 1st Ring Road, Chengdu, 610041, China.
Arch Virol. 2017 Feb;162(2):523-527. doi: 10.1007/s00705-016-3119-x. Epub 2016 Oct 25.
An enterovirus (EV) strain, designated as SWUN-AB001, was isolated in the Qinghai-Tibetan Plateau from a yak with severe diarrheal disease. The complete genome of strain SWUN-AB001 was 7,382 bp in length and shared 35.1-68.5% nt identities with bovine EVs belonging to a candidate new type EV-F7. Using the sequence difference values in the VP1 gene as a criterion for demarcating a new serotype/genotype in the Enterovirus genus, strain SWUN-AB001 had only a 71.1% nt and a 79.2% aa identity, in the VP1 region, with the most closely matched EV, further indicating that a new type of EV had been identified. Phylogenetic analysis of the nt sequence of the viral polyprotein and of VP1 genes demonstrated that the virus fell within the EV-F cluster, but was located in a unique lineage. Furthermore, a large-scale surveillance study indicated that the prevalence of this EV in yaks was 31.05% (95% CI = 25.5-37.6%) in 235 animals with diarrhea and 24.13% (95% CI = 17.4-32.4%) in 116 healthy yaks. However, there was no significant difference in virus prevalence between diarrheal and healthy samples. Interestingly, in the Tibet region, diarrheal feces had a higher incidence of EVs than feces of healthy yaks (odd ratios = 6.03, 95% CI = 1.93-18.86), indicating that the incidence of EV was potentially correlated with the clinical symptom of diarrhea in yaks.
从青藏高原一头患有严重腹泻疾病的牦牛体内分离出一株肠道病毒（EV），命名为SWUN-AB001。SWUN-AB001毒株的全基因组长度为7382 bp，与属于候选新型EV-F7型的牛源肠道病毒的核苷酸同一性为35.1%-68.5%。以VP1基因中的序列差异值作为划分肠道病毒属新血清型/基因型的标准，SWUN-AB001毒株在VP1区域与最匹配的肠道病毒的核苷酸同一性仅为71.1%，氨基酸同一性为79.2%，进一步表明已鉴定出一种新型肠道病毒。对病毒多聚蛋白和VP1基因的核苷酸序列进行系统发育分析表明，该病毒属于EV-F簇，但位于一个独特的谱系中。此外，一项大规模监测研究表明，在235头腹泻牦牛中，这种肠道病毒的流行率为31.05%（95%置信区间=25.5-37.6%），在116头健康牦牛中为24.13%（95%置信区间=17.4-32.4%）。然而，腹泻样本和健康样本中的病毒流行率没有显著差异。有趣的是，在西藏地区，腹泻粪便中肠道病毒的发生率高于健康牦牛的粪便（优势比=6.03，95%置信区间=1.93-18.86），这表明肠道病毒的发生率可能与牦牛腹泻的临床症状相关。
