中国南方某农村地区人与猪戊型肝炎病毒的检测和部分序列分析

Detection and analysis of partial sequences isolated from human and swine in rural area of southern China

目的 调查中国南方某农村地区戊型肝炎病毒(HEV)人株与猪株的相关性。方法应用逆转录-巢式聚合酶链法(RT-nPCR)对一般人群中HEV-IgM阳性者、急性戊型肝炎患者和当地某养猪场的猪进行HEV RNA检测，并对HEV RNA阳性标本进行克隆测序和序列分析。结果 132份猪粪便标本中13份为HEV RNA阳性；26份lgM阳性一般人群血清标本中有4份HEV RNA阳性；4例急性戊型肝炎患者中有1例的血清和粪便标本为阳性。序列分析发现该地区HEV人株与猪株在ORE2部分区域的核苷酸序列同源性为89.3%～100.0%，这10株HEV序列与HEV Ⅰ型、Ⅱ型、Ⅲ型和Ⅳ型在同一区域的核苷酸序列的同源性分别为78.7%～84.7%、83.3%～85.3%、76.0%～80.0%和84.7%～95.3%。结论 该地区人群及猪群中流行的HEV同属基因Ⅳ型。

Objective To study the genotype of swines isolated from humans and their relationships with hepatitis E virus（HEV） in the rural areas of southern China. Methods Specimens collected from normal people with HEV-IgM positive, acute hepatitis E patients and from swine in the same area were detected for HEV RNA using RT-nPCR with ORF2 primers. The positive PCR products were cloned and sequenced. Results 13 out of the 132 samples from swine stool, 4 of 26 HEV-IgM positive sera of normal people and 1 of 4 acute hepatitis E patients＇ stool sample and sera were tested positive for HEV RNA. Data from sequence analysis showed that the identity at nucleotide level was 89.3%-100.0% among the 10 isolates which shared 78.7%-84.7%,83.3%-85.3%,76.0% 80.0% and 84.7%-95.3% nucleotide sequence identity with HEV genotype Ⅰ , Ⅱ, Ⅲ and Ⅳ respectively in the region （nt6317-6466）. Conclusion HEV circulating in humans and swine in the area belonged to genotype Ⅳ.