title: Efficacy of the rhesus rotavirus-based quadrivalent vaccine in infants and young children in Venezuela.
abstract: BACKGROUND
  Rotaviruses are the principal known etiologic agents of severe diarrhea among infants and young children worldwide. Although a rhesus rotavirus-based quadrivalent vaccine is highly effective in preventing severe diarrhea in developed countries, in developing countries its efficacy has been less impressive. We thus conducted a catchment study in Venezuela to assess the efficacy of the vaccine against dehydrating diarrhea.
  
  
  METHODS
  In this randomized, double-blind, placebo-controlled trial, 2207 infants received three oral doses of the quadrivalent rotavirus vaccine (4x10(5) plaque-forming units per dose) or placebo at about two, three, and four months of age. During approximately 19 to 20 months of passive surveillance, episodes of gastroenteritis were evaluated at the hospital.
  
  
  RESULTS
  The vaccine was safe, although 15 percent of the vaccinated infants had febrile episodes (rectal temperature, > or =38.1 degrees C) during the six days after the first dose, as compared with 7 percent of the controls (P<0.001). However, the vaccine gave 88 percent protection against severe diarrhea caused by rotavirus and 75 percent protection against dehydration, and produced a 70 percent reduction in hospital admissions. Overall, the efficacy of the vaccine against a first episode of rotavirus diarrhea was 48 percent. Horizontal transmission of vaccine virus was demonstrated in 15 percent of the vaccine recipients and 13 percent of the placebo recipients with rotavirus-positive diarrhea.
  
  
  CONCLUSIONS
  In this study in a developing country, the quadrivalent rhesus rotavirus-based vaccine induced a high level of protection against severe diarrheal illness caused by rotavirus.
authors.affiliation: Instituto de Biomedicina/Universidad Central de Venezuela/Ministerio de Sanidad, Fuvesin, Caracas.
authors.forename: I
authors.initials: I
authors.lastname: Pérez-Schael
authors.forename: M J
authors.initials: MJ
authors.lastname: Guntiñas
authors.forename: M
authors.initials: M
authors.lastname: Pérez
authors.forename: V
authors.initials: V
authors.lastname: Pagone
authors.forename: A M
authors.initials: AM
authors.lastname: Rojas
authors.forename: R
authors.initials: R
authors.lastname: González
authors.forename: W
authors.initials: W
authors.lastname: Cunto
authors.forename: Y
authors.initials: Y
authors.lastname: Hoshino
authors.forename: A Z
authors.initials: AZ
authors.lastname: Kapikian
mesh_terms: D000914:Antibodies, Viral / Q000097:blood; D003681:Dehydration / Q000209:etiology / Q000517:prevention & control; D003906:Developing Countries; D003968:Diarrhea, Infantile / Q000150:complications / Q000517:prevention & control* / Q000821:virology; D018562:Disease Transmission, Infectious; D004311:Double-Blind Method; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D008297:Male; D012401:Rotavirus / Q000145:classification / Q000276:immunology; D012400:Rotavirus Infections / Q000150:complications / Q000517:prevention & control* / Q000635:transmission; D022243:Rotavirus Vaccines; D014687:Venezuela; D014765:Viral Vaccines / Q000009:adverse effects / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D022243:Rotavirus Vaccines; D014765:Viral Vaccines; C052014:rhesus rotavirus vaccine