An investigation of district spatial variations of childhood diarrhoea and fever morbidity in Malawi

Although diarrhoea and malaria are among the leading causes of child mortality and morbidity in Sub-Saharan Africa, few detailed studies have examined the patterns and determinants of these ailments in the most affected communities. In this paper, we investigate the spatial distribution of observed diarrhoea and fever prevalence in Malawi using individual data for 10,185 children from the 2000 Malawi Demographic and Health survey. We highlight inequalities in child health by mapping the residual district spatial effects using a geo-additive probit model that simultaneously controls for spatial dependence in the data and potential nonlinear effects of covariates. The residual spatial effects were modelled via a Bayesian approach. For both ailments, we were able to identify a distinct district pattern of childhood morbidity. In particular, the results suggest that children living in the capital city are less affected by fever, although this is not true for diarrhoea, where some urban agglomerations are associated with a higher childhood morbidity risk. The spatial patterns emphasize the role of remoteness as well as climatic, environmental, and geographic factors on morbidity. The fixed effects show that for diarrhoea, the risk of child morbidity appears to be lower among infants who are exclusively breastfed than among those who are mixed-fed. However, exclusive breastfeeding was not found to have a protective effect on fever. An important socio-economic factor for both diarrhoea and fever morbidity was parental education, especially maternal educational attainment. Diarrhoea and fever were both observed to show an interesting association with child's age. We were able to discern the continuous worsening of the child morbidity up to 8–12 months of age. This deterioration set in right after birth and continues, more or less linearly until 8–12 months, before beginning to decline thereafter. Independent of other factors, a separate spatial process produces district inequalities in child's health.