title: Changes in Rotavirus Genotypes before and after Vaccine Introduction: a Multicenter, Prospective Observational Study in Three Areas of Japan.
abstract: In Japan, monovalent and pentavalent rotavirus (RV) vaccines were approved in 2011 and 2012, respectively. To monitor changes in the RV genotypes before and after vaccine introduction, we performed a prospective observational study among children (＜ 5 years) with gastroenteritis who tested RV-positive on antigen rapid tests. Stool samples were collected from 3 different sites in Japan: Tsu City, Mie Prefecture; Kurashiki City, Okayama Prefecture; and Isumi City, Chiba Prefecture. RV genotypes were determined using reverse transcription-polymerase chain reaction. In Tsu City, G3P[8] was dominant (61.0-77.1%) before vaccine introduction, but decreased after introduction. Meanwhile, in an inverse proportion to the decrease in G3P[8], G1P[8] increased until the 2013/14 season, when a sudden predominance of G2P[4] (100%) occurred. A similar trend was observed in Kurashiki City in terms of the extent of reduction in G3P[8] and the emergence of G2P[4]. In Isumi City, G1P[8] was dominant (70.3%) before vaccine introduction, and G9P[8] became predominant (83.3%) in the 2013/14 season. To determine whether the genotype changes are attributable to vaccines or natural epidemiological changes, ongoing continuous monitoring of the RV genotypes is required.
authors.affiliation: Department of Pediatrics, Kawasaki Medical School.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Infectious Disease Surveillance Center, National Institute of Infectious Diseases.
authors.forename: Hajime
authors.initials: H
authors.lastname: Kamiya
authors.affiliation: Department of Pediatrics, National Mie Hospital.
authors.forename: Kazutoyo
authors.initials: K
authors.lastname: Asada
authors.affiliation: Department of Pediatrics, National Mie Hospital.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Suga
authors.affiliation: Department of Pediatrics, Mie Chuo Medical Center.
authors.forename: Masaru
authors.initials: M
authors.lastname: Ido
authors.affiliation: Umemoto Children's Clinic.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Umemoto
authors.affiliation: Department of Pediatrics, Kawasaki Medical School.
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Ouchi
authors.affiliation: Department of Pediatrics, Kameda Medical Center.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ito
authors.affiliation: Sotobo Children's Clinic.
authors.forename: Haruo
authors.initials: H
authors.lastname: Kuroki
authors.affiliation: Department of Pediatrics, Kawasaki Medical School.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakano
authors.affiliation: Department of Virology and Parasitology, Fujita Health University School of Medicine.
authors.forename: Koki
authors.initials: K
authors.lastname: Taniguchi
mesh_terms: D002675:Child, Preschool; D005243:Feces / Q000821:virology; D005260:Female; D005838:Genotype; D060005:Genotyping Techniques; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan / Q000453:epidemiology; D008297:Male; D017720:Molecular Epidemiology; D011446:Prospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012401:Rotavirus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D012400:Rotavirus Infections / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology*; D022243:Rotavirus Vaccines / Q000008:administration & dosage* / Q000276:immunology*
chemical_list: D022243:Rotavirus Vaccines
keywords: gastroenteritis; genotype; rotavirus; vaccine