Measles outbreak in South Africa, 2003 - 2005

Autor: McMorrow, ML, Gebremedhin, G, van den Heever, J, Kezaala, R, Harris, BN, Nandy, R
Jazyk: angličtina
Rok vydání: 2010
Zdroj: South African Medical Journal; Vol 99, No 5 (2009)
ISSN: 2078-5135
0256-9574
Popis: Objectives. Measles was virtually eliminated in South Africa following control activities in 1996/7. However, from July 2003 to November 2005, 1 676 laboratory-confirmed measles cases were reported in South Africa. We investigated the outbreak’s cause and the role of HIV.Design. We traced laboratory-confirmed case-patients residingin the Johannesburg metropolitan (JBM) and O R Tambo districts. We interviewed laboratory- or epidemiologically confirmed case-patients or their caregivers to determine vaccination status and, in JBM, HIV status. We calculated vaccine effectiveness using the screening method.Setting. Household survey in JBM and O R Tambo districts.Outcome measures. Vaccine effectiveness, case-fatality rate, andhospitalisations. Results. In JBM, 109 case-patients were investigated. Of the 57 case-patients eligible for immunisation, 27 (47.4%) were vaccinated. Fourteen (12.8%) case-patients were HIV infected, 46 (42.2%) were HIV uninfected, and 49 (45.0%) had unknown HIV status. Among children aged 12 - 59 months, vaccine effectiveness was 85% (95% confidence interval (CI): 63, 94) for all children, 63% for HIV infected, 75% for HIV uninfected, and 96% for children with unknown HIV status. (Confidence intervals were not calculated for sub-groupsowing to small sample size.) In O R Tambo district, 157 casepatientswere investigated. Among the 138 case-patients eligible for immunisation, 41 (29.7%) were vaccinated. Vaccine effectiveness was 89% (95% CI 77, 95).Conclusions. The outbreak’s primary cause was failure to vaccinate enough of the population to prevent endemic measles transmission. Although vaccine effectiveness might have been lower in HIV-infected than in uninfected children, population vaccine effectiveness remained high.
Databáze: OpenAIRE