Epidemiological description of cholera outbreak in Mpumalanga Province, South Africa, December 2008-March 2009

Background: In developing countries, cholera often occurs in large-scale outbreaks and causes high burden of disease and leads to death in some cases. The purpose of the study was to describe and characterise cholera cases, and also to identify environmental health factors that contributed to the outbreak. Methods: A descriptive, retrospective study was conducted to describe the outbreak and to identify environmental health factors that contributed to the outbreak. The preliminary assessment was done by means of Microsoft Excel 2003 and thereafter followed by statistical analysis of the database using Epi Info statistical software. STATA 11 was used for the calculation of correlation coefficient between cholera and sanitation factors. Results: A total of 6 278 cholera positive cases were recorded between December 2008 and March 2009 with 30 deaths, which translate into a case-fatality rate of 0.48%. The overall attack rate for cholera during the outbreak was 3.3 per 1 000. The cumulative incidence was the highest (0.55 per 100 persons) in Mbombela sub-district with 4 049 cases and lowest (0.02 per 100 persons) in uMjindi with 120 cases recorded. On average the male-to-female case ratio was 1:1.5 across all age groups. Most cases 79% (n = 5011) had access to tap water, 12% (n = 784) depended on rivers while 9% (n = 9) cases sourced water from streams, boreholes and springs. Conclusions: This study, along with evidence from the epidemiology of other diarrhoeal diseases, suggests that safe water supply, adequate sanitation and community awareness campaigns, are the best means of preventing cholera, as well as other diarrhoeal diseases in large-scale outbreaks.