Malaria hotspots in Rwanda - relative influence of climate variability and interventions

Despite intense malaria interventions and associated decline of malaria transmission in Rwanda; potential for malaria transmission remain in highly endemic areas. As response, an integrated malaria control was introduced based on local ecology, malaria epidemiology and socio-economic factors. This strategy intends to sustain the achievements in malaria reduction by effective interventions in the areas of the most needs. Pinpointing malaria hotspots can be therefore seen as a well timed support towards local initiative in malaria elimination. As malaria is both sensitive to environmental and socio-economic factors, it is equally important to assess the extent to which malaria is the interplay of climate variability and interventions in Rwanda highlands. Malaria and interventions related data were gathered from Rwandan Ministry of Health. Climate data were provided by Rwanda Meteorological Agency. Hotspot analysis was used to examine the spatial clusters of malaria. Correlation and regression analysis were also performed to test the association between climatic variables and malaria; and to investigate the relative influence of climate and interventions in two research areas with differing malaria endemicity. Persistent hotspots partially overlap with the locations of malaria vector breeding sites in eastern and south-east lower lands. In unstable transmission highlands, a moderate association between climate variability and malaria was evidenced. In high endemic and stable malaria transmission settings, a lack of a strong association between malaria and climate variability was identified. Those findings suggest that malaria interventions would have masked the expected relationship between climate and malaria in highly endemic areas. Maintaining malaria interventions in highlands and more targeting intervention to malaria hotspots can be an efficient way of reducing in Rwanda.