Environmental predictors of malaria infection in Sussundenga, Mozambique

Abstract

Background Malaria is highly sensitive to environmental conditions, including climate variability and land use practices. Ecologically, Sussundenga district has a significantly lower elevation compared to the Zimbabwe border and a more tropical climate compared to southern and northern Mozambique due to high seasonal rainfall. We aimed to evaluate the effects of climate and environmental factors at the household level on rapid diagnostic test results for Malaria in Sussundenga, Mozambique. Methods To understand this association, we collected publicly available United States Geological Survey satellite data on elevation, vegetation, and land use cover. Additionally, we collected satellite data on day and night land surface temperatures and evapotranspiration which we assessed at 1- and 2-week lags. We spatially and temporally joined these data with malaria infection data at the household level. Using this database, we assessed whether these environmental factors were good predictors for having a positive rapid diagnostic test result using spatio-temporal models that accounted for the underlying correlation structure. Risk factor surveillance is an important tool for controlling the spread of infectious diseases. Results Of the environmental factors that were investigated in this study, landcover was found to be most strongly associated with malaria risk, and we found that the estimated effect of grassland or cropland landcover on malaria risk varies depending on whether the house has holes in the wall. Conclusions The results from modeling of the ecological predictors of malaria infection and spatial maps provided in this study could aid in developing frameworks to mitigate malaria transmission and predict future malaria transmission in this region. Understanding how environmental changes impacts malaria transmission and infection at the household level may have important implications for vector control and disease surveillance strategies utilized by the district.