PLoS Medicine (Jan 2013)

Malaria burden and artemisinin resistance in the mobile and migrant population on the Thai-Myanmar border, 1999-2011: an observational study.

  • Verena I Carrara,
  • Khin Maung Lwin,
  • Aung Pyae Phyo,
  • Elizabeth Ashley,
  • Jacher Wiladphaingern,
  • Kanlaya Sriprawat,
  • Marcus Rijken,
  • Machteld Boel,
  • Rose McGready,
  • Stephane Proux,
  • Cindy Chu,
  • Pratap Singhasivanon,
  • Nicholas White,
  • François Nosten

DOI
https://doi.org/10.1371/journal.pmed.1001398
Journal volume & issue
Vol. 10, no. 3
p. e1001398

Abstract

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BackgroundThe Shoklo Malaria Research Unit has been working on the Thai-Myanmar border for 25 y providing early diagnosis and treatment (EDT) of malaria. Transmission of Plasmodium falciparum has declined, but resistance to artesunate has emerged. We expanded malaria activities through EDT and evaluated the impact over a 12-y period.Methods and findingsBetween 1 October 1999 and 30 September 2011, the Shoklo Malaria Research Unit increased the number of cross-border (Myanmar side) health facilities from two to 11 and recorded the number of malaria consultations. Changes in malaria incidence were estimated from a cohort of pregnant women, and prevalence from cross-sectional surveys. In vivo and in vitro antimalarial drug efficacy were monitored. Over this period, the number of malaria cases detected increased initially, but then declined rapidly. In children under 5 y, the percentage of consultations due to malaria declined from 78% (95% CI 76-80) (1,048/1,344 consultations) to 7% (95% CI 6.2-7.1) (767/11,542 consultations), pConclusionsDespite the emergence of resistance to artesunate in P. falciparum, the strategy of EDT with artemisinin-based combination treatments has been associated with a reduction in malaria in the migrant population living on the Thai-Myanmar border. Although limited by its observational nature, this study provides useful data on malaria burden in a strategically crucial geographical area. Alternative fixed combination treatments are needed urgently to replace the failing first-line regimen of mefloquine and artesunate. Please see later in the article for the Editors' Summary.