BACKGROUND: A measles outbreak occurred in Maroua, Cameroon, from January 2008 to April 2009. In accordance with recent World Health Organization guidelines, an outbreak-response immunization (ORI) was conducted in January 2009. The aim of this study was to investigate the causes of the epidemic in order to guide vaccination strategies. METHODS: We performed a stratified household-based survey using cluster sampling to determine measles vaccination coverage in children aged 9 months to 15 years. We defined 3 strata based on measles incidence. Next, we performed a case-control study to measure vaccine effectiveness (VE). Cases were obtained from health center registries. Controls were selected among respondents to the coverage survey. RESULTS: The vaccination-coverage survey included 2963 children in total. The overall routine vaccination coverage was 74.1% (95% confidence interval [CI]: 70.0%-78.3%). Measles incidence was inversely proportional to routine vaccination coverage, with high incidence associated with coverage of 71% and low incidence associated with coverage of 84%. The overall VE was 94% (95% CI, 86.7%-97.4%). After the ORI in January 2009, the coverage was >90% in all strata and measles incidence declined rapidly. DISCUSSION: Our results confirm that insufficient vaccination coverage was the main reason for this epidemic. The ORI conducted in January 2009 contributed both to control the epidemic and to increase the vaccination coverage to desirable levels.
BACKGROUND: A measles outbreak occurred in Maroua, Cameroon, from January 2008 to April 2009. In accordance with recent World Health Organization guidelines, an outbreak-response immunization (ORI) was conducted in January 2009. The aim of this study was to investigate the causes of the epidemic in order to guide vaccination strategies. METHODS: We performed a stratified household-based survey using cluster sampling to determine measles vaccination coverage in children aged 9 months to 15 years. We defined 3 strata based on measles incidence. Next, we performed a case-control study to measure vaccine effectiveness (VE). Cases were obtained from health center registries. Controls were selected among respondents to the coverage survey. RESULTS: The vaccination-coverage survey included 2963 children in total. The overall routine vaccination coverage was 74.1% (95% confidence interval [CI]: 70.0%-78.3%). Measles incidence was inversely proportional to routine vaccination coverage, with high incidence associated with coverage of 71% and low incidence associated with coverage of 84%. The overall VE was 94% (95% CI, 86.7%-97.4%). After the ORI in January 2009, the coverage was >90% in all strata and measles incidence declined rapidly. DISCUSSION: Our results confirm that insufficient vaccination coverage was the main reason for this epidemic. The ORI conducted in January 2009 contributed both to control the epidemic and to increase the vaccination coverage to desirable levels.
Authors: James L Goodson; Eric Wiesen; Robert T Perry; Ondrej Mach; Mary Kitambi; Mary Kibona; Elizabeth T Luman; K Lisa Cairns Journal: Vaccine Date: 2009-08-03 Impact factor: 3.641
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Authors: Lise Grout; Andrea Minetti; Northan Hurtado; Gwenola François; Florence Fermon; Anne Chatelain; Géza Harczi; Jean de Dieu Ilunga Ngoie; Alexandra N'Goran; Francisco J Luquero; Rebecca F Grais; Klaudia Porten Journal: BMC Infect Dis Date: 2013-05-22 Impact factor: 3.090
Authors: Lise Grout; Nolwenn Conan; Aitana Juan Giner; Northan Hurtado; Florence Fermon; Alexandra N'Goran; Emmanuel Grellety; Andrea Minetti; Klaudia Porten; Rebecca F Grais Journal: BMC Public Health Date: 2014-02-21 Impact factor: 3.295