Early detection and response to meningococcal disease epidemics in sub-Saharan Africa: appraisal of the WHO strategy
OBJECTIVE: To assess the sensitivity, specificity and predictive value positive of the WHO threshold strategy for detecting meningococcal disease epidemics in sub-Saharan Africa and to estimate the impact of the strategy on an epidemic at district level.METHODS: Data on meningitis cases at the district level were collected weekly from health minist