Household environmental health hazards' effect on under-five mortality in sub-Saharan Africa: What can we learn from the Demographic and Health Survey?

Household environmental health hazards or simply household health hazards (HHH) are pathogens and chemicals in the household that can cause health problems. In this study, we assess their effect on under-five mortality (U5MR) in 12 sub-Saharan African countries, using data from the Demographic and Health Surveys. Referring to the principal component analysis approach, we measure the HHH by the following indicators: source of water and its location, type of toilet facility, flooring material, type of wall, type of roof and type of cooking fuel. In an unadjusted multilevel discrete-time hazard model, we find that HHH affect positively child mortality in 9 of the 12 countries, whereas this effect presented itself only in 4 countries when controlling for other covariates. However, using a model with interaction between the child's age and HHH, we find it interesting that increasing levels of the HHH are consistently associated with increasing risk of death during 24-59 months after birth in eight countries. Future researches are needed to decipher the mechanisms behind these findings, whether explained by the accumulation of hazardous environment in early childhood, or frequent contact with noxious environments at a later stage of childhood, or both.