2010 年日本甲型肝炎散发疫情的流行病学和遗传学分析。

Epidemiological and genetic analyses of a diffuse outbreak of hepatitis A in Japan, 2010.

机构信息

Department of Virology II, National Institute of Infectious Diseases, Japan.

出版信息

J Clin Virol. 2012 Mar;53(3):219-24. doi: 10.1016/j.jcv.2011.11.008. Epub 2011 Dec 22.

DOI:10.1016/j.jcv.2011.11.008

PMID:22196871

Abstract

BACKGROUND

Hepatitis A virus (HAV) is still one of the most common causative agents of acute hepatitis in Japan. Although a relatively small number of annual acute hepatitis A cases (approximately 100-150, 0.78-1.17 per million) were recently reported, a larger number of cases (346, 2.71 per million) were reported in 2010.

OBJECTIVES

To investigate the causes of the 2010 HAV resurgence in Japan by using molecular epidemiological and genetic analyses.

STUDY DESIGN

HAV specimens were obtained from 61 cases from 22 different prefectures. These viral specimens were genotyped by PCR amplification and sequencing of the VP1/2A region of HAV genome.

RESULTS

Phylogenetic analysis revealed that 61 HAV strains could be divided into three genotypes: IA (44 cases), IB (1 case) and IIIA (16 cases). The IA genotype consisted of two genomic sub-lineages. The sequences of one of the two IA sub-lineages (corresponding to 31 cases) were very similar, 26 of these 31 isolates had 100% identity. The other IA sub-lineage corresponded to strains endemic to Japan. The sequences of Japanese IIIA strains were similar to those of strains that caused a large epidemic in the Republic of Korea from 2007 to 2009.

CONCLUSIONS

The resurgence of HAV in 2010 can be attributed to importation of two newly emerged HAV genotypes.

摘要

背景

甲型肝炎病毒（HAV）仍然是日本最常见的急性肝炎病原体之一。尽管最近报告的每年急性甲型肝炎病例数量相对较少（约 100-150 例，每百万人 0.78-1.17 例），但在 2010 年报告的病例数量更多（346 例，每百万人 2.71 例）。

目的

通过分子流行病学和遗传分析研究日本 2010 年甲型肝炎病毒反弹的原因。

研究设计

从日本 22 个不同县的 61 例病例中获得 HAV 标本。通过 PCR 扩增和 HAV 基因组 VP1/2A 区域的测序对这些病毒标本进行基因分型。

结果

系统进化分析显示，61 株 HAV 株可分为三个基因型：IA（44 例）、IB（1 例）和 IIIA（16 例）。IA 基因型包含两个基因组亚系。两个 IA 亚系之一的序列（对应 31 例）非常相似，其中 31 个分离株中有 26 个具有 100%的同一性。另一个 IA 亚系对应于日本地方性流行的菌株。日本 IIIA 株的序列与 2007 年至 2009 年期间在大韩民国引起大规模流行的菌株相似。