Water, Sanitation and Hygiene, and cholera epidemiology: An integrated evaluation in the countries of the Lake Chad basin (2011)

Authors/Organisations: Pierre-Yves Oger and Bertrand Sudre/UNICEF

Year: 2011

Country: Lake Chad basin (Nigeria, Niger, Tchad, Cameroun)

A multi-sectoral strategy is needed to ensure preparedness and response to cholera epidemics. It must be based on epidemiology knowledges at different scales and times, and on the involvement of all the WASH stakeholders. After the sub-regional cholera outbreak in 2010, this study aims at proposing integrated WASH and Health response by first describing the epidemiology of cholera in the Chad Lake Basin and secondly by suggesting actions of prevention, preparedness and response to cholera epidemics. Actions must be coordinated and supported by all the relevant WASH and Health stakeholders.

The Lake Chad Basin is a specific area with a climate typical of Sudan and the Sahel. The lakeside area and the lake’s tributaries as well as a marked seasonality structure the agriculture, pastoral and transhumance activities that take place here. In this essentially rural space, cross-border communication channels attract commercial activities. Population displacements occur between the several major agglomerations where dense neighbourhoods have structural difficulties with water conveyance and sanitation.

The first cholera epidemic in the Chad lake Basin was notified in 1971, when the seventh pandemic spread to West Africa. The year 1991 next marked a turning point with a heightened frequency of annual epidemics. The geographical study of the last ten years confirms this tendency and illustrates the cross-border character of the epidemic processes and their spread. The retrospective analysis of the risk factors on the regional level highlighted factors linked to water, sanitation and hygiene. According to data from Cameroon and Nigeria, the presence of open wells on a large scale is significantly associated with cholera. The local transmission mechanisms are less well known, but late access to care, combined with population displacements (particularly across borders) and funeral traditions are factors of vulnerability in the spread of the disease that have been described since the first epidemics. The analysis of the epidemiological surveillance system led to the proposal of a set of national and sub-regional focuses for work on early warning systems. Community surveillance and cross-border cooperation are the two main issues.

Based on the analysis, the following recommendations are proposed:

• Establishing cross-border public health collaboration to prepare for the spread of epidemics,
• Adopting a Shield/Sword strategy with emergency rapid response initiatives;
• Considering social and human dimensions in the elaboration of the prevention and control strategies and to seek for the direct involvement of the communities,
• Developing operational research programs to optimize the quality of prevention and cholera epidemic control programs.

The report below is available in english. Click here to find the french version: Evaluation intégrée Eau-Hygiène-Assainissement et Epidémiologie du choléra dans les pays du bassin du lac Tchad (2011)