title: Detection and genetic characterization of rotavirus infections in non-hospitalized children with acute gastroenteritis in Japan, 2007-2009.
abstract: The molecular epidemiology of rotavirus infections in non-hospitalized children in five different regions (Sapporo, Saga, Tokyo, Osaka, and Maizuru) of Japan during 2007-2009 was investigated. Overall, rotavirus was detected in 156 out of 1008 (15.5%) specimens. The rotavirus infection in 2007-2008 (19.3%) was higher than those in 2008-2009 (12.1%). G1P[8] was the most prevalent (62.8%), followed by G3P[8] (21.8%), G9P[8] (14.7%), and G2P[4] (0.7%). Interestingly, the number of G3P[8] strains increased threefold from the former season (2006-2007) from 7.3% to 21.8%, whereas G2P[4] and G9P[8] decreased from 11.4% to 0.7% and 20.3% to 14.7%, respectively. In the phylogenetic analysis, G3 rotaviruses were closely related to "the new variant G3" 5091 strain, which previously emerged in Japan and China. G9 viruses isolated in 2007-2008 were genetically close to the Thai strain, while those isolated in 2008-2009 had a close relationship with Chinese strains. G1 viruses appeared to be more similar to the recently reported G1 strain in China. Nucleotide sequence analysis of 33 P[8]-nontypeable strains revealed 5 nucleotide mismatches at the primer binding site. Based on previously reported (2003-2007) and current (2007-2009) data of rotavirus surveillance in the five areas of Japan, it was revealed that in Sapporo, Osaka, and Maizuru, G1P[8] and G3P[8] were detected at high frequencies, ranging from 47.2 to 57.7% and 31.7 to 47.4%, respectively. In Tokyo, G1P[8] (47.4%) was the predominant strain, followed by G9P[8] (20.6%), whereas in Saga, G3P[8] (38.9%) and G9P[8] (36.1%) were identified as the most dominant types. None of G9P[8] was detected in Sapporo. This study highlights the genetic diversity and the significance of rotavirus diarrhea in Japan.
authors.affiliation: Department of Developmental Medical Sciences, School of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Wisoot
authors.initials: W
authors.lastname: Chan-it
authors.forename: Aksara
authors.initials: A
authors.lastname: Thongprachum
authors.forename: Shuvra Kanti
authors.initials: SK
authors.lastname: Dey
authors.forename: Tung Gia
authors.initials: TG
authors.lastname: Phan
authors.forename: Pattara
authors.initials: P
authors.lastname: Khamrin
authors.forename: Shoko
authors.initials: S
authors.lastname: Okitsu
authors.forename: Shuichi
authors.initials: S
authors.lastname: Nishimura
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kikuta
authors.forename: Tsuneyoshi
authors.initials: T
authors.lastname: Baba
authors.forename: Atsuko
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Kumiko
authors.initials: K
authors.lastname: Sugita
authors.forename: Shintaro
authors.initials: S
authors.lastname: Hashira
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tajima
authors.forename: Shinichi
authors.initials: S
authors.lastname: Ishida
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizuguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ushijima
mesh_terms: D000293:Adolescent; D000956:Antigens, Viral / Q000235:genetics*; D001483:Base Sequence; D036022:Capsid Proteins / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D005759:Gastroenteritis / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012401:Rotavirus / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology*; D017423:Sequence Analysis, RNA
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; C060339:VP4 protein, Rotavirus; C050779:VP7 protein, Rotavirus