title: Hospital-based surveillance to evaluate the impact of rotavirus vaccination in São Paulo, Brazil.
abstract: BACKGROUND
  Brazil implemented routine immunization with the human rotavirus vaccine, Rotarix, in 2006 and vaccination coverage reached 81% in 2008 in São Paulo. Our aim was to assess the impact of immunization on the incidence of severe rotavirus acute gastroenteritis (AGE).
  
  
  METHODS
  We performed a 5-year (2004-2008) prospective surveillance at a sentinel hospital in São Paulo, with routine testing for rotavirus in all children less than 5 years of age hospitalized with AGE. Genotypes of positive samples were determined by reverse transcription polymerase chain reaction.
  
  
  RESULTS
  During the study, 655 children hospitalized with AGE were enrolled; of whom 169 (25.8%) were positive for rotavirus. In the postvaccine period, a 59% reduction in the number of hospitalizations of rotavirus AGE and a 42.2% (95% confidence interval [CI], 18.6%-59.0%; P = 0.001) reduction in the proportion of rotavirus-positive results among children younger than 5 years were observed, with the greatest decline among infants (69.2%; 95% CI, 24.7%-87.4%; P = 0.004). Furthermore, the number of all-cause hospitalizations for AGE was reduced by 29% among children aged <5 years. The onset and peak incidences of rotavirus AGE occurred 3 months later in the 2007 and 2008 seasons compared with previous years. Genotype G2 accounted for 15%, 70%, and 100% of all cases identified, respectively, in 2006, 2007, and 2008.
  
  
  CONCLUSIONS
  After vaccine implementation, a marked decline in rotavirus AGE hospitalizations was demonstrated among children younger than 5 years of age, with the greatest reduction in the age groups targeted for vaccination. The predominance of genotype G2P[4] highlights the need of continued postlicensure surveillance studies.
authors.affiliation: Division of Pediatric Infectious Diseases, Department of Pediatrics, Santa Casa School of Medical Sciences, São Paulo, Brazil. masafadi@uol.com.br
authors.forename: Marco Aurelio Palazzi
authors.initials: MA
authors.lastname: Sáfadi
authors.forename: Eitan Naaman
authors.initials: EN
authors.lastname: Berezin
authors.forename: Veridiana
authors.initials: V
authors.lastname: Munford
authors.forename: Flavia Jaqueline
authors.initials: FJ
authors.lastname: Almeida
authors.forename: Jose Cassio
authors.initials: JC
authors.lastname: de Moraes
authors.forename: Cid Fernando
authors.initials: CF
authors.lastname: Pinheiro
authors.forename: Maria Lucia
authors.initials: ML
authors.lastname: Racz
mesh_terms: D000208:Acute Disease; D001938:Brazil / Q000453:epidemiology; D016009:Chi-Square Distribution; D002675:Child, Preschool; D005243:Feces / Q000821:virology; D005759:Gastroenteritis / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D011159:Population Surveillance; D011446:Prospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012401:Rotavirus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D012400:Rotavirus Infections / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology; D022243:Rotavirus Vaccines / Q000008:administration & dosage* / Q000276:immunology; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000276:immunology
chemical_list: C492457:RIX4414 vaccine; D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated