Epidemiology of cholera outbreaks and socio-economic characteristics of the communities in the fishing villages of Uganda: 2011-2015

Background: The communities in fishing villages in the Great Lakes Region of Africa and particularly in Uganda experience recurrent cholera outbreaks that lead to considerable mortality and morbidity. We evaluated cholera epidemiology and population characteristics in the fishing villages of Uganda to better target prevention and control interventions of cholera and contribute to its elimination from those communities. Methodology/Principal findings: We conducted a prospective study between 2011–15 in fishing villages in Uganda. We collected, reviewed and documented epidemiological and socioeconomic data for 10 cholera outbreaks that occurred in fishing communities located along the African Great Lakes and River Nile in Uganda. These outbreaks caused 1,827 suspected cholera cases and 43 deaths, with a Case-Fatality Ratio (CFR) of 2.4%. Though the communities in the fishing villages make up only 5–10% of the Ugandan population, they bear the biggest burden of cholera contributing 58% and 55% of all reported cases and deaths in Uganda during the study period. The CFR was significantly higher among males than females (3.2% vs. 1.3%, p = 0.02). The outbreaks were seasonal with most cases occurring during the months of April-May. Male children under age of 5 years, and 5–9 years had increased risk. Cholera was endemic in some villages with well-defined “hotspots”. Practices predisposing communities to cholera outbreaks included: the use of contaminated lake water, poor sanitation and hygiene. Additional factors were: ignorance, illiteracy, and poverty. Conclusions/Significance: Cholera outbreaks were a major cause of morbidity and mortality among the fishing communities in Uganda. In addition to improvements in water, sanitation, and hygiene, oral cholera vaccines could play an important role in the prevention and control of these outbreaks, particularly when targeted to high-risk areas and populations. Promotion and facilitation of access to social services including education and reduction in poverty should contribute to cholera prevention, control and elimination in these communities. Author summary: Cholera, though a preventable and treatable disease, remains a major cause of morbidity and mortality in the Great Lakes Region of Africa, including Uganda. The communities in the fishing villages constitute 5–10% of the total Ugandan population. Most fishing villages are located along Lakes Victoria, Albert and Edward and the River Nile. During the study period, 2011–2015 these villages were responsible for over 50% of the reported annual cholera cases and deaths in Uganda. The CFR was significantly higher among males than females (3.2% vs. 1.3%, p = 0.02). Our study is the first to systematically describe the epidemiology of these outbreaks and socioeconomic characteristics of communities in the fishing villages in Uganda. Our study found that persons in the fishing villages were at increased risk of cholera outbreaks due to poor access to safe water, sanitation, and hygiene. Furthermore, the villages had similar population characteristics such as illiteracy, ignorance regarding cholera transmission, poverty and constant population migration. In addition to improvements in water, sanitation, and hygiene, complementary use of oral cholera vaccines could play an important role, particularly when targeted to high-risk areas and populations. As a long term strategy, improvements in education and reduction in poverty should contribute to cholera prevention, control and elimination in the fishing villages and Uganda as whole.