Spatial synchrony of malaria outbreaks in a highland region of Ethiopia

Michael C. Wimberly, Alemayehu Midekisa, Paulos Semuniguse, Hiwot Teka, Geoffrey M. Henebry, Ting Wu Chuang, Gabriel B. Senay

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

To understand the drivers and consequences of malaria in epidemic-prone regions, it is important to know whether epidemics emerge independently in different areas as a consequence of local contingencies, or whether they are synchronised across larger regions as a result of climatic fluctuations and other broad-scale drivers. To address this question, we collected historical malaria surveillance data for the Amhara region of Ethiopia and analysed them to assess the consistency of various indicators of malaria risk and determine the dominant spatial and temporal patterns of malaria within the region. We collected data from a total of 49 districts from 1999-2010. Data availability was better for more recent years and more data were available for clinically diagnosed outpatient malaria cases than confirmed malaria cases. Temporal patterns of outpatient malaria case counts were correlated with the proportion of outpatients diagnosed with malaria and confirmed malaria case counts. The proportion of outpatients diagnosed with malaria was spatially clustered, and these cluster locations were generally consistent from year to year. Outpatient malaria cases exhibited spatial synchrony at distances up to 300km, supporting the hypothesis that regional climatic variability is an important driver of epidemics. Our results suggest that decomposing malaria risk into separate spatial and temporal components may be an effective strategy for modelling and forecasting malaria risk across large areas. They also emphasise both the value and limitations of working with historical surveillance datasets and highlight the importance of enhancing existing surveillance efforts.

Original languageEnglish
Pages (from-to)1192-1201
Number of pages10
JournalTropical Medicine and International Health
Volume17
Issue number10
DOIs
Publication statusPublished - Oct 2012
Externally publishedYes

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Ethiopia
Malaria
Disease Outbreaks
Outpatients

Keywords

  • Climate
  • Environment
  • Malaria epidemics
  • Spatial autocorrelation
  • Spatial synchrony
  • Surveillance

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health
  • Infectious Diseases
  • Parasitology

Cite this

Wimberly, M. C., Midekisa, A., Semuniguse, P., Teka, H., Henebry, G. M., Chuang, T. W., & Senay, G. B. (2012). Spatial synchrony of malaria outbreaks in a highland region of Ethiopia. Tropical Medicine and International Health, 17(10), 1192-1201. https://doi.org/10.1111/j.1365-3156.2012.03058.x

Spatial synchrony of malaria outbreaks in a highland region of Ethiopia. / Wimberly, Michael C.; Midekisa, Alemayehu; Semuniguse, Paulos; Teka, Hiwot; Henebry, Geoffrey M.; Chuang, Ting Wu; Senay, Gabriel B.

In: Tropical Medicine and International Health, Vol. 17, No. 10, 10.2012, p. 1192-1201.

Research output: Contribution to journalArticle

Wimberly, MC, Midekisa, A, Semuniguse, P, Teka, H, Henebry, GM, Chuang, TW & Senay, GB 2012, 'Spatial synchrony of malaria outbreaks in a highland region of Ethiopia', Tropical Medicine and International Health, vol. 17, no. 10, pp. 1192-1201. https://doi.org/10.1111/j.1365-3156.2012.03058.x
Wimberly, Michael C. ; Midekisa, Alemayehu ; Semuniguse, Paulos ; Teka, Hiwot ; Henebry, Geoffrey M. ; Chuang, Ting Wu ; Senay, Gabriel B. / Spatial synchrony of malaria outbreaks in a highland region of Ethiopia. In: Tropical Medicine and International Health. 2012 ; Vol. 17, No. 10. pp. 1192-1201.
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