title: Outbreak of aseptic meningitis associated with mass vaccination with a urabe-containing measles-mumps-rubella vaccine: implications for immunization programs.
abstract: A mass immunization campaign with a Urabe-containing measles-mumps-rubella vaccine was carried out in 1997 in the city of Salvador, northeastern Brazil, with a target population of children aged 1-11 years. There was an outbreak of aseptic meningitis following the mass campaign. Cases of aseptic meningitis were ascertained through data collected from the records of children admitted to the local referral hospital for infectious diseases between March and October of 1997, using previously defined eligibility criteria. Vaccination histories were obtained through home visits or telephone calls. Eighty-seven cases fulfilled the study criteria. Of those, 58 cases were diagnosed after the vaccination campaign. An elevated risk of aseptic meningitis was observed 3 weeks after Brazil's national vaccination day compared with the risk in the prevaccination period (relative risk = 14.3; 95% confidence interval: 7.9, 25.7). This result was confirmed by a case series analysis (relative risk = 30.4; 95% confidence interval: 11.5, 80.8). The estimated risk of aseptic meningitis was 1 in 14,000 doses. This study confirms a link between measles-mumps-rubella vaccination and aseptic meningitis. The authors discuss the implications of this for the organization and planning of mass immunization campaigns.
authors.affiliation: Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, Brazil.
authors.forename: I
authors.initials: I
authors.lastname: Dourado
authors.forename: S
authors.initials: S
authors.lastname: Cunha
authors.forename: M G
authors.initials: MG
authors.lastname: Teixeira
authors.forename: C P
authors.initials: CP
authors.lastname: Farrington
authors.forename: A
authors.initials: A
authors.lastname: Melo
authors.forename: R
authors.initials: R
authors.lastname: Lucena
authors.forename: M L
authors.initials: ML
authors.lastname: Barreto
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D006801:Humans; D015994:Incidence; D007223:Infant; D008458:Measles Vaccine / Q000009:adverse effects*; D022542:Measles-Mumps-Rubella Vaccine; D008582:Meningitis, Aseptic / Q000453:epidemiology* / Q000209:etiology / Q000821:virology; D009108:Mumps Vaccine / Q000009:adverse effects*; D009109:Mumps virus / Q000472:pathogenicity; D011358:Product Surveillance, Postmarketing; D012189:Retrospective Studies; D012307:Risk Factors; D012411:Rubella Vaccine / Q000009:adverse effects*; D014505:Urban Population; D014611:Vaccination / Q000009:adverse effects*; D017778:Vaccines, Combined / Q000009:adverse effects
chemical_list: D008458:Measles Vaccine; D022542:Measles-Mumps-Rubella Vaccine; D009108:Mumps Vaccine; D012411:Rubella Vaccine; D017778:Vaccines, Combined