title: Molecular analysis of hepatitis A virus strains obtained from patients with acute hepatitis A in Mongolia, 2004-2013.
abstract: Despite the high endemicity of hepatitis A virus (HAV) in Mongolia, the genetic information on those HAV strains is limited. Serum samples obtained from 935 patients with acute hepatitis in Ulaanbaatar, Mongolia during 2004-2013 were tested for the presence of HAV RNA using reverse transcription-PCR with primers targeting the VP1-2B region (481 nucleotides, primer sequences at both ends excluded). Overall, 180 patients (19.3%) had detectable HAV RNA. These 180 isolates shared 94.6-100% identity and formed four phylogenetic clusters within subgenotype IA. One or three representative HAV isolates from each cluster exhibited 2.6-3.9% difference between clusters over the entire genome. Cluster 1 accounted for 65.0% of the total, followed by Cluster 2 (30.6%), Cluster 3 (3.3%), and Cluster 4 (1.1%). Clusters 1 and 2 were predominant throughout the observation period, whereas Cluster 3 was undetectable in 2009 and 2013 and Cluster 4 became undetectable after 2009. The Mongolian HAV isolates were closest to those of Chinese or Japanese origin (97.7-98.5% identities over the entire genome), suggesting the evolution from a common ancestor with those circulating in China and Japan. Further molecular epidemiological analyses of HAV infection are necessary to investigate the factors underlying the spread of HAV and to implement appropriate prevention measures in Mongolia.
authors.affiliation: National Institute of Medicine, Ministry of Health and Ministry of Science Education, Ulaanbaatar, Mongolia.|National Center for Communicable Diseases, Ministry of Health, Ulaanbaatar, Mongolia.
authors.forename: Bira
authors.initials: B
authors.lastname: Tsatsralt-Od
authors.affiliation: National Institute of Medicine, Ministry of Health and Ministry of Science Education, Ulaanbaatar, Mongolia.
authors.forename: Nachin
authors.initials: N
authors.lastname: Baasanjav
authors.affiliation: National Center for Communicable Diseases, Ministry of Health, Ulaanbaatar, Mongolia.
authors.forename: Dulmaa
authors.initials: D
authors.lastname: Nyamkhuu
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohnishi
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan.
authors.forename: Tominari
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Nagashima
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nishizawa
authors.affiliation: Division of Virology, Department of Infection and Immunity, Jichi Medical University School of Medicine, Tochigi, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Okamoto
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006506:Hepatitis A / Q000453:epidemiology* / Q000821:virology*; D030041:Hepatitis A virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D008986:Mongolia / Q000453:epidemiology; D010802:Phylogeny; D012367:RNA, Viral / Q000097:blood; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017385:Sequence Homology; D055815:Young Adult
chemical_list: D012367:RNA, Viral
keywords: Mongolia; full-length genome; genotype; hepatitis A virus; phylogenetic tree