Guinea worm disease in Ayod, Upper Nile Province, southern Sudan: a cross-sectional study

Upper Nile Province is one of the four main endemic areas for Guinea worm disease in the Sudan. In December 1994, a survey was conducted in the village of Ayod where the disease is endemic, to investigate morbidity and local knowledge of transmission and prevention. Interviews were conducted in households selected by standard cluster sampling procedures and of the 759 people examined, 156 (20.6%) had Guinea worm lesions. Adjusted odds ratios were used to estimate the relative risk for people with different personal or household characteristics in a multivariate analysis. After controlling for the possible confounding effects of other study variables, having a filter in the household, gender, and lack of knowledge about transmission and about prevention, were not associated with lesions. Only two variables were significantly associated with Guinea worm disease: getting water from a source other than a well increased the risk by a factor of 2.3, and being aged 5 years or more increased the risk by a factor of 31.1. This study demonstrates the clear association between the source of water for drinking and Guinea worm disease found elsewhere. We suggest the provision of reliable sources of pure drinking water and health education are the most suitable long-term preventive measures. The Sudan now represents the greatest challenge to the goal of global eradication of Guinea worm disease, following the reduction in cases in Nigeria. The continuing civil war and insecurity in southern Sudan hinder the implementation of an effective water programme and other control measures, but the potential benefits through reduced incapacity and improved agricultural productivity are considerable.