A Spatial Autocorrelation Analysis of Cholera Patterns and Social Risk Factors in Nigeria

Cholera has remained a public health issue since the seventh pandemic, especially in countries like Nigeria, with the disease occurring both in sporadic and epidemic scales. Based on the World Health Organisation’s record, Nigeria alone has reported 380,698 (28,898) cases and deaths between 1991 and 2011 ? the highest from Africa. This study investigated the geographic pattern of cholera cases and deaths in Nigeria, in order to determine its risk factors and areas that are more at risk. A Global Moran Index spatial autocorrelation was employed to determine the clustering of cholera across the country. Disease rate ratios were computed by categorising the 36 states and Federal Capital Territory of the country in to four strata based on geographical location; population density; absolute poverty; and adult literacy. The result indicates a significant positive spatial autocorrelation of cholera in all the twelve years investigated (Moran I: 0.211, p: < 0.007). Clustering is more pronounced in the northern part of the country, most especially in the northeast, while less clustering is found in the southern part of the country.