A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots

  1. Philip Bejon  Is a corresponding author
  2. Thomas N Williams
  3. Christopher Nyundo
  4. Simon I Hay
  5. David Benz
  6. Peter W Gething
  7. Mark Otiende
  8. Judy Peshu
  9. Mahfudh Bashraheil
  10. Bryan Greenhouse
  11. Teun Bousema
  12. Evasius Bauni
  13. Kevin Marsh
  14. David L Smith
  15. Steffen Borrmann
  1. Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kenya
  2. Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, United Kingdom
  3. University of Oxford, United Kingdom
  4. University of California, San Francisco, United States
  5. London School of Hygiene and Tropical Medicine, United Kingdom
  6. 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.

Article and author information

Author details

  1. Philip Bejon

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    For correspondence
    pbejon@kemri-wellcome.org
    Competing interests
    The authors declare that no competing interests exist.
  2. Thomas N Williams

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Christopher Nyundo

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    Competing interests
    The authors declare that no competing interests exist.
  4. Simon I Hay

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. David Benz

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Peter W Gething

    University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Mark Otiende

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    Competing interests
    The authors declare that no competing interests exist.
  8. Judy Peshu

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    Competing interests
    The authors declare that no competing interests exist.
  9. Mahfudh Bashraheil

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    Competing interests
    The authors declare that no competing interests exist.
  10. Bryan Greenhouse

    University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  11. Teun Bousema

    London School of Hygiene and Tropical Medicine, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  12. Evasius Bauni

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    Competing interests
    The authors declare that no competing interests exist.
  13. Kevin Marsh

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    Competing interests
    The authors declare that no competing interests exist.
  14. David L Smith

    John Hopkins Malaria Research Institute, Baltimore, United States
    Competing interests
    The authors declare that no competing interests exist.
  15. Steffen Borrmann

    Kilifi KEMRI-Wellcome Trust Collaborative Research Programme, Kilifi, Kenya
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Mercedes Pascual, University of Michigan, United States

Ethics

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.

Version history

  1. Received: December 19, 2013
  2. Accepted: April 1, 2014
  3. Accepted Manuscript published: April 24, 2014 (version 1)
  4. Version of Record published: April 29, 2014 (version 2)

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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  1. Philip Bejon
  2. Thomas N Williams
  3. Christopher Nyundo
  4. Simon I Hay
  5. David Benz
  6. Peter W Gething
  7. Mark Otiende
  8. Judy Peshu
  9. Mahfudh Bashraheil
  10. Bryan Greenhouse
  11. Teun Bousema
  12. Evasius Bauni
  13. Kevin Marsh
  14. David L Smith
  15. Steffen Borrmann
(2014)
A micro-epidemiological analysis of febrile malaria in Coastal Kenya showing hotspots within hotspots
eLife 3:e02130.
https://doi.org/10.7554/eLife.02130

Share this article

https://doi.org/10.7554/eLife.02130

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