2020—2021年庄河市甲型肝炎病毒流行株基因组特征分析

Genomic characteristics of hepatitis A virus epidemic strains in Zhuanghe from 2020 to 2021

目的分析2020—2021年庄河市环境污水中甲型肝炎病毒(hepatitis A virus,HAV)基因组特征,比较其与病例标本HAV基因组相似性。方法收集2021年庄河市7—12月18份污水处理厂进水口污水样本(环境污水),提取病毒RNA,逆转录后采用巢式PCR对VP1-2A区进行扩增,测序拼接获得5条HAV核苷酸序列(321 bp)。使用生物信息学软件进行系统进化分析。结果2021年环境污水样本HAV均为ⅠA亚型,VP1-2A区核苷酸序列同源性为98.7%~100%。与2020年庄河市甲肝病例样本的核苷酸序列同源性为97.8%~100%,进化上分为2个分支。结论ⅠA亚型为庄河市环境污水HAV的优势基因型,与病例样本的基因组存在差异,也有部分毒株的基因组完全一致。通过比较环境污水中HAV核酸与病例样本核酸的相似性,可更好地了解HAV的循环,以便对甲肝的流行病学监测作出早期预警。

Objective To analyze the genomic characteristics of hepatitis A virus(HAV)in environmental sewage in Zhuanghe from 2020 to 2021 and compare them with those in case samples.Methods Eighteen sewage samples(environmental sewage)were collected from the entry point of the sewage treatment plant in Zhuanghe from July to December 2021,and the viral RNA was extracted.After reverse transcription,VP1-2A region was amplified by nested PCR,sequenced and spliced.The five HAV nucleotide sequences(321 bp)obtained were analyzed for phylogenetic tree by using bioinformatics software.Results The HAV of environmental sewage samples in 2021 were all 1A subtype,and the nucleotide sequence homology of VP1-2A region was 98.7%-100%.The nucleotide sequence homology was 97.8%-100%with that of the hepatitis A case samples from Zhuanghe in 2020,which could be evolutionarily divided into two branches.Conclusion Subtype 1A was the dominant genotype of HAV in environmental sewage in Zhuanghe,which was different from the genome of the case sample,and also had the same genome of some strains.By comparing the similarities between HAV nucleic acid in environmental sewage and that in case samples,we can better understand the circulation of HAV,so as to make an early warning for the epidemiological monitoring of hepatitis A.