云南和广东省流行性出血病病毒血清6型毒株(EHDV-6)的分离与遗传特性

李占鸿; 杨振兴; 林栩慧; 吕敏娜; 肖雷; 寇美玲; 廖德芳; 朱建波; 杨恒; 李华春

doi:10.7671/j.issn.1001-411X.201908033

云南和广东省流行性出血病病毒血清6型毒株(EHDV-6)的分离与遗传特性

Isolation and genetic characteristics of epidemic hemorrhagic disease virus serotype 6 (EHDV-6) strains from Yunnan and Guangdong Provinces

摘要

摘要:
目的分离流行于我国南方地区的流行性出血病病毒血清6型毒株(EHDV-6)，掌握分离毒株的遗传特征。

方法对设立于我国云南和广东省的哨兵动物定期采血，进行EHDV感染情况监测与病毒分离培养。通过血清中和试验确定分离EHDV的血清型，采用一步法RT-PCR对分离的EHDV-6毒株基因节段2、3、6(Seg-2、-3、-6)进行扩增与序列分析。

结果 2012—2016年，从云南省和广东省的哨兵动物中分离出25株EHDV毒株，其中，11株为EHDV-6型。中国EHDV-6型毒株的Seg-2、-3与-6均属Eastern型，核酸序列相似性分别为99.1%、98.9%和98.8%，在系统发生树上分别聚为1个独立的中国支系。在日本引起疫病暴发的EHDV-6型毒株与中国EHDV-6型毒株具有最近的亲缘关系。日本EHDV-6型毒株在系统发生树上处于中国支系内部，Seg-2、Seg-3与中国毒株的核酸序列相似性分别为98.5%和93.9%。

结论云南和广东省流行的EHDV-6型毒株核酸与氨基酸序列高度相似；日本和中国的EHDV-6型毒株具有最近的亲缘关系，提示中日之间可能存在EHDV的流动。研究结果为进一步开展我国EHDV-6型毒株流行病学分析、致病性、病原学诊断与疫苗制备等研究提供了基础。

Abstract:
Objective To isolate epidemic hemorrhagic disease virus serotype 6 (EHDV-6) strains prevalent in southern China, and investigate the genetic characteristics of the isolated strains.

Method Blood samples were collected from sentinel animals in Yunnan and Guangdong Provinces in China. EHDV infection was monitored and the virus was isolated. The serum types of isolated strains were determined by serum neutralization test, and segments 2, 3 and 6 (Seg-2, -3 and -6) of EHDV-6 isolated strains were amplified by one-step RT-PCR and subsequently sequenced.

Result From 2012 to 2016, 25 EHDV strains were isolated from sentinel animals in Yunnan and Guangdong Provinces and 11 strains of them were EHDV-6. Seg-2, -3 and -6 of Chinese EHDV-6 strains were of Eastern topotype, and the nucleic acid sequence similarities were 99.1%, 98.9% and 98.8% respectively, which were clustered into an independent Chinese branch on the phylogenetic tree. Chinese EHDV-6 strains had the closest relationship with the EHDV-6 strains which caused epidemic outbreaks in Japan. The Japanese EHDV-6 strain was within the Chinese branch on the phylogenetic tree. The similarities of nucleic acid sequences of Seg-2 and Seg-3 between the Japanese and Chinese strains were 98.5% and 93.9% respectively.

Conclusion The sequences of EHDV-6 strains prevalent from Yunnan and Guangdong Provinces are highly similar. The closest genetic relationship between Japanese and Chinese EHDV-6 strains suggests that there may be flow of EHDV between China and Japan. The results provide a basis for further research on epidemiological analysis, pathogenicity, etiological diagnosis and vaccine preparation of EHDV-6 strains in China.

HTML全文

参考文献(26)

施引文献

资源附件(0)