Measles outbreak in South Africa, 2003-2005.
OBJECTIVE
Measles was virtually eliminated in South Africa following control activities in 1996/7. However, from July 2003 to November 2005, 1676 laboratory-confirmed measles cases were reported in South Africa. We investigated the outbreak's cause and the role of HIV.


METHODS
We traced laboratory-confirmed case-patients residing in 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.


METHODS
Household survey in JBM and O. R. Tambo districts. Outcome measures. Vaccine effectiveness, case-fatality rate, and hospitalisations.


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-groups owing to small sample size.) In O. R. Tambo district, 157 case-patients were 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.
McMorrow
Meredith L
ML
Malaria Branch Division of Parasitic Diseases, National Center for Zoonotic, Vector-Borne, and Enteric Diseases, Centers for Disease Control and Prevention and United States Public Health Service, Atlanta, USA. MMcmorrow@cdc.gov
Gebremedhin
Goitom
G
van den Heever
Johann
J
Kezaala
Robert
R
Harris
Bernice N
BN
Nandy
Robin
R
Strebel
Peter
P
Jack
Abdoulie
A
Cairns
K Lisa
KL
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D016358:Contact Tracing; D004196:Disease Outbreaks; D015658:HIV Infections / Q000150:complications; D006801:Humans; D007223:Infant; D008457:Measles / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission; D008458:Measles Vaccine; D012189:Retrospective Studies; D012307:Risk Factors; D013019:South Africa / Q000453:epidemiology; D055815:Young Adult
D008458:Measles Vaccine