Cholera outbreaks in sub-Saharan Africa during 2010-2019: a descriptive analysis.

• Cholera outbreaks affected 2% of the sub-Saharan Africa populations in the 2010 decade. • 692 outbreaks were identified in 492 districts with a systematic definition. • Larger outbreaks were associated with longer durations and lower reported mortality. • Population density was not always associated with severe cholera outbreak outcomes. • Surveillance needs to be enhanced to improve cholera outbreak monitoring. Cholera remains a public health threat but is inequitably distributed across sub-Saharan Africa. Lack of standardized reporting and inconsistent outbreak definitions limit our understanding of cholera outbreak epidemiology. From a database of cholera incidence and mortality, we extracted data from sub-Saharan Africa and reconstructed outbreaks of suspected cholera starting in January 2010 to December 2019 based on location-specific average weekly incidence rate thresholds. We then described the distribution of key outbreak metrics. We identified 999 suspected cholera outbreaks in 744 regions across 25 sub-Saharan African countries. The outbreak periods accounted for 1.8 billion person-months (2% of the total during this period) from January 2010 to January 2020. Among 692 outbreaks reported from second-level administrative units (e.g., districts), the median attack rate was 0.8 per 1000 people (interquartile range (IQR), 0.3-2.4 per 1000), the median epidemic duration was 13 weeks (IQR, 8-19), and the median early outbreak reproductive number was 1.8 (range, 1.1-3.5). Larger attack rates were associated with longer times to outbreak peak, longer epidemic durations, and lower case fatality risks. This study provides a baseline from which the progress toward cholera control and essential statistics to inform outbreak management in sub-Saharan Africa can be monitored. [ABSTRACT FROM AUTHOR]