戊型肝炎病毒基因型与致病性研究进展

Research progress on genotyping and pathogenicity of hepatitis E virus

戊型肝炎病毒（hepatitis E Virus,HEV）为直径27~34nm、球型且无包膜的单股正链RNA病毒[1]。HEV基因组全长约7.2×103 bp,包含3个开放读码框（open reading frame,ORF 1~3）,分别编码不同的蛋白,在病毒入侵、组装与释放等过程中起重要作用[2]。HEV主要经粪-口途径传播,也有报道经血液或母婴垂直传播[3-5]。核酸序列分析表明,HEV至少可分为4个基因型,基因1型和2型只感染人,基因3型和4型为人畜共患病原体,既能感染人,也能感染猪、

Recent studies on hepatitis E virus（HEV）have discovered many novel strains from different sources.Currently,at least four major distinct genotypes of the virus（HEV1-4）have been identified.Genotypes 1and 2are restricted to humans,mainly causing epidemics of acute hepatitis.Genotypes 3and4 are zoonotic and are responsible for sporadic cases of infection.It has been showed that HEV usually causes asymptomatic and subclinical infections.HEV-1and HEV-2are considered inherently more virulent to humans than HEV-3and HEV-4.Yet in recent years,there have been reports that genotype 3HEV infections may count for the prolonged or chronic infections among immunocompromised individuals but the mechanism is still unclear.