Cholera outbreaks in sub-Saharan Africa during 2010-2019: A Descriptive Analysis

Abstract

Background: Cholera remains a public health threat, but is inequitably distributed, especially affecting areas without universal access to safe water and sanitation, including much of sub-Saharan Africa. Lack of standardized reporting and inconsistent outbreak definitions limit our understanding of cholera outbreak epidemiology. Methods: We curated a database of cholera incidence and mortality from sub-Saharan Africa from 2010 to 2020 and developed methods to reconstruct epidemic curves. We then described the distribution of key outbreak metrics, including outbreak size and duration. Results: We identified 999 suspected cholera outbreaks in 744 unique regions across 25 sub-Saharan Africa countries, and outbreak periods accounted for 1.8 billion person-months (2% of the total during this period) from January 2010 through January 2020. Among the 692 outbreaks reported from second-level administrative units (e.g., districts), the median attack rate was 0.8 per 1,000 people (IQR, 0.3-2.4 per 1,000), 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). Rural outbreaks had more than twice the case fatality risk than urban ones (median of 1.8% versus 0.8%). Larger attack rates were associated with longer times to outbreak peak, longer epidemic durations, and lower case fatality risks. Conclusions: Despite reporting gaps and the limitations of analyzing outbreaks by administrative units, this work provides a baseline from which to monitor progress towards cholera control and essential statistics to inform outbreak management and emergency response in sub-Saharan Africa.

Water Shortages: Cause of Water Safety in Sub-Saharan Africa

“…This may explain why 83% of the total deaths due to cholera were from the SSA region [43]. Additionally, a curated database of cholera incidence in SSA from 2010 to 2020 identified 999 suspected cholera outbreaks across 25 SSA countries [44]. Most of the major outbreaks of this disease occurred in countries such as Nigeria, Cameroon, the Democratic Republic of Congo, Kenya, Ethiopia, and Sudan [42][43][44].…”

“…Additionally, a curated database of cholera incidence in SSA from 2010 to 2020 identified 999 suspected cholera outbreaks across 25 SSA countries [44]. Most of the major outbreaks of this disease occurred in countries such as Nigeria, Cameroon, the Democratic Republic of Congo, Kenya, Ethiopia, and Sudan [42][43][44]. Notably, the collective outbreaks in four countries alone (Democratic Republic of the Congo, Ethiopia, Cameroon, and South Sudan) represented 65% of total outbreaks that occurred in the entire SSA [44].…”

“…Most of the major outbreaks of this disease occurred in countries such as Nigeria, Cameroon, the Democratic Republic of Congo, Kenya, Ethiopia, and Sudan [42][43][44]. Notably, the collective outbreaks in four countries alone (Democratic Republic of the Congo, Ethiopia, Cameroon, and South Sudan) represented 65% of total outbreaks that occurred in the entire SSA [44]. Besides poor sanitation and hygiene, floods have been recognized as one of the major contributing factors of cholera outbreaks in SSA [45].…”

Prioritizing interventions for cholera control in Kenya, 2015–2020

“…Cholera remains a public health threat to over one billion people globally [ 1 – 3 ], and the majority of cases reported to the World Health Organization (WHO) are from sub-Saharan Africa. [ 4 ] Cholera was first reported in Kenya in 1971 and Kenya has since experienced outbreaks regularly every few years, with the most recent wave of outbreaks beginning in December 2014 [ 5 – 7 ]. Kenya reported the “index case” of the epidemic wave onset in Eastern and Southern Africa in December 2014, which spread to other African nations including Tanzania, Uganda and South Sudan [ 8 ].…”

Spatiotemporal modelling of cholera and implications for its control, Uvira, Democratic Republic of the Congo

“…Cholera outbreaks continue to impact communities that lack access to safe water and adequate sanitation. (1)(2)(3)(4) In these communities, cholera's relatively high reproduction number and short median incubation period (1.4 days, 95% credible interval 1.3-1.6) (1,5) mean that an initial cluster can rapidly propagate across space. During outbreaks, household fecal-oral transmission through contaminated water, food, and fomites and direct contact becomes substantial and therefore, interventions to prevent infection of household contacts can reduce household transmission.…”