Changing Water-Sanitation Determinants of Cholera over Two Decades in Bangladesh

Cholera is a leading global public health threat, especially in developing countries. This study aimed to determine the changing determinants of cholera related to water-sanitation practices between 1994-1998 and 2014-2018 in Dhaka, Bangladesh. Data of all cause diarrhea cases were extracted from the Diarrheal Disease Surveillance System of the International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, and analysis was performed among three groups: Vibrio cholerae detected as sole pathogen, V. cholerae detected as mixed infection, and detection of no common enteropathogen in stool specimens (reference). Using sanitary toilet, drinking tap water, drinking boiled water, family size greater than five, and slum dwelling were the main exposures. Overall, 3,380 (20.30%) and 1,290 (9.69%) patients were positive for V. cholerae during 1994-1998 and 2014-2018, respectively. In 1994-1998, use of sanitary toilet (adjusted odds ratio [aOR]: 0.86, 95% CI: 0.76-0.97) and drinking tap water (aOR: 0.81, 95% CI: 0.72-0.92) were found to be negatively associated and in 2014-2018, drinking tap water (aOR: 1.47, 95% CI: 1.21-1.78) and slum dwelling (aOR: 1.43, 95% CI: 1.10-1.86) were found to be positively associated with V. cholerae infection after adjusting for age, sex, monthly income, and seasonality. Because the determinants of cholera such as drinking tap water can change over time in developing cities, ameliorating the water, sanitation, and hygiene (WASH) situation is of paramount importance. In addition, in settings such as urban slums, where long-term WASH monitoring might be difficult to achieve, mass vaccination with oral cholera vaccine should be introduced to control cholera.