Epidemiological analysis of a cholera outbreak in pastoral communities in the Somali region of Ethiopia

Cholera is an acute diarrhea disease caused by infection of the intestine with the toxigenic bacterium Vibrio cholerae serogroup O1 or O139. It is a waterborne disease of global health importance with an estimated 3 to 5 million cases and over 100,000 deaths annually. Our key objective was to analyze the epidemiology of a cholera outbreak in the Somali region of Ethiopia, which took place in 2017, using an electronic surveillance cholera database. We investigated 7 cholera-affected-districts. In total, 4115 cases of cholera were reported, of which 3846 (93.5%) records were eligible. Three thousand eight hundred forty six cases and 112 deaths from 11 Cholera Treatment Centres (CTC) were reported, with attack risk (AR) of 103 per 10,000 populations, and a case fatality rate (CFR) of 2.95 %. The CFR was 3.1 in females and 2.8 in males. People with travel history to a cholera affected area were five times more likely to die from cholera (OR 5.00; 95% CI 3.23-7.87). People with severe dehydration were seven times more likely to die (OR 7.80; 95%CI 2.44-47.60). The age-specific CFR was highest (4.9%) in the 2-4 years’ age group, and lowest (1.7%) in the 15-44 age range. Pastoral communities ought to be provided access to clean and safe drinkable water. There must be availability of anti-cholera vaccines to tackle the burden of the disease, for example, the OCV recommended by the Global Task Force on Cholera Control.