Measles incidence, vaccine efficacy, and mortality in two urban African areas with high vaccination coverage

Peter Aaby, K Knudsen, T G Jensen, J Thårup, A Poulsen, Morten Sodemann, M C da Silva, H Whittle

Research output: Contribution to journalJournal articleResearchpeer-review


Measles incidence, vaccine efficacy, and mortality were examined prospectively in two districts in Bissau where vaccine coverage for children aged 12-23 months was 81% (Bandim 1) and 61% (Bandim 2). There was little difference in cumulative measles incidence before 9 months of age (6.1% and 7.6%, respectively). Between 9 months and 2 years of age, however, 6.1% contracted measles in Bandim 1 and 13.7% in Bandim 2. Even adjusting for vaccination status, incidence was significantly higher in Bandim 2 (relative risk 1.6, P = .04). Even though 95% of the children had measles antibodies after vaccination, vaccine efficacy was not more than 68% (95% confidence interval [CI] 39%-84%) and was unrelated to age at vaccination. Unvaccinated children had a mortality hazard ratio of 3.0 compared with vaccinated children (P = .002), indicating a protective efficacy against death of 66% (CI 32%-83%) of measles vaccination. These data suggest that it will be necessary to vaccinate before age 9 months to control measles in hyperendemic urban African areas.
Original languageEnglish
JournalJournal of Infectious Diseases
Issue number5
Pages (from-to)1043-8
Number of pages6
Publication statusPublished - 1990



  • Age Factors
  • Antibodies, Viral
  • Cohort Studies
  • Guinea-Bissau
  • Humans
  • Incidence
  • Infant
  • Measles
  • Measles Vaccine
  • Measles virus
  • Prospective Studies
  • Regression Analysis
  • Urban Population
  • Vaccination

Cite this