title: Prevalence and molecular epidemiology of noroviruses in hospitalized children with acute gastroenteritis in Rio de Janeiro, Brazil, 2004.
abstract: BACKGROUND
  The role of noroviruses (NoV) as a cause of gastroenteritis outbreaks is well documented; however, the importance of NoV infections in hospitalized children is not well established. The aim of this study was to determine the prevalence and the genetic diversity of NoV in hospitalized children.
  
  
  METHODS
  Three-hundred eighteen fecal samples were collected from January to December 2004, from children with acute gastroenteritis in 3 public hospitals in Rio de Janeiro, Brazil. The prevalence and genetic diversity of NoV was carried out by using genome amplification and sequencing of polymerase and capsid genes.
  
  
  RESULTS
  NoV infections were detected in 65 (20%) of the samples, of which 11 (4%) were mixed infections with rotavirus. Infants up to 1-year-old were the most affected and a peak of virus detection was observed in autumn and spring seasons. Dehydration and diarrhea were the inclusion criterion; coughing (51%), vomiting (33%), and fever (22%) were the main clinical manifestations. Phylogenetic analysis showed that Genogroup II and GII/4 were prevalent. Two potential recombinant strains based in the different clustering pattern were observed.
  
  
  CONCLUSIONS
  This study demonstrated the importance of NoV infections causing severe acute gastroenteritis in hospitalized children in Rio de Janeiro, Brazil. Molecular epidemiology surveillance determining the circulation pattern of different genotypes and recombinant strains is helpful for designing prevention strategies of NoV transmission in children. Studies concerning the prevalence and the molecular epidemiology of gastroenteric viruses in hospitalized children are particularly important to evaluate the impact of the rotavirus vaccine in Brazil.
authors.affiliation: Laboratory of Comparative Virology, Department of Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil. matias@ioc.fiocruz.br
authors.forename: Matías
authors.initials: M
authors.lastname: Victoria
authors.forename: Filipe Aníbal
authors.initials: FA
authors.lastname: Carvalho-Costa
authors.forename: Marcos Bryan
authors.initials: MB
authors.lastname: Heinemann
authors.forename: José Paulo
authors.initials: JP
authors.lastname: Leite
authors.forename: Marize
authors.initials: M
authors.lastname: Miagostovich
mesh_terms: D001938:Brazil / Q000453:epidemiology; D017250:Caliciviridae Infections / Q000453:epidemiology* / Q000821:virology*; D002675:Child, Preschool; D005243:Feces / Q000821:virology; D005759:Gastroenteritis / Q000453:epidemiology* / Q000821:virology*; D006760:Hospitalization; D006801:Humans; D007223:Infant; D017720:Molecular Epidemiology; D029322:Norovirus / Q000235:genetics*; D015995:Prevalence; D012621:Seasons; D013997:Time Factors