A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots
- Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kenya
- Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, United Kingdom
- University of Oxford, United Kingdom
- University of California, San Francisco, United States
- London School of Hygiene and Tropical Medicine, United Kingdom
- John Hopkins Malaria Research Institute, United States
Abstract
Malaria transmission is spatially heterogeneous. This reduces the efficacy of control strategies, but focusing control strategies on clusters or 'hotspots' of transmission may be highly effective. Among 1,500 homesteads in coastal Kenya we calculated a) the fraction of febrile children with positive malaria smears per homestead, and b) the mean age of children with malaria per homestead. These two measures were inversely correlated, indicating that children in homesteads at higher transmission acquire immunity more rapidly. This inverse correlation increased gradually with increasing spatial scale of analysis, and hotspots of febrile malaria were identified at every scale. We found hotspots within hotspots, down to the level of an individual homestead. Febrile malaria hotspots were temporally unstable, but 4km radius hotspots could be targeted for one month following one month periods of surveillance.
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Human subjects: Informed consent for participation was obtained, and specific ethical approval was obtained from the KEMRI Ethical Review Committee (SSC Protocol No. 2413: Spatial Epidemiology of Malaria Cases in the Kilifi District Demographic Surveillance Area). The KEMRI ethical review committee required that participants consent for participation in research and for their data to be stored, but does not require a further explicit statement consenting to publication. Our institutional guidelines would require this only in the event that individuals were identifiable in the publication.
Copyright
© 2014, Bejon et al.
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots
eLife 3:e02130.
https://doi.org/10.7554/eLife.02130
Further reading
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