Research Abstract


Indian Ocean Dipole drives malaria resurgence in East African highlands

2012年2月16日 Scientific Reports 2 : 269 doi: 10.1038/srep00269


橋爪 真弘1, Luis Fernando Chaves2 & 皆川 昇1

  1. 長崎大学 熱帯医学研究所
  2. 北海道大学大学院 環境科学研究院
Malaria resurgence in African highlands in the 1990s has raised questions about the underlying drivers of the increase in disease incidence including the role of El-Niño-Southern Oscillation (ENSO). However, climatic anomalies other than the ENSO are clearly associated with malaria outbreaks in the highlands. Here we show that the Indian Ocean Dipole (IOD), a coupled ocean-atmosphere interaction in the Indian Ocean, affected highland malaria re-emergence. Using cross-wavelet coherence analysis, we found four-year long coherent cycles between the malaria time series and the dipole mode index (DMI) in the 1990s in three highland localities. Conversely, we found a less pronounced coherence between malaria and DMI in lowland localities. The highland/lowland contrast can be explained by the effects of mesoscale systems generated by Lake Victoria on its climate basin. Our results support the need to consider IOD as a driving force in the resurgence of malaria in the East African highlands.