Volume 68, Issue 3
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


We have analyzed artemisinin sensitivity in isolates obtained from patients in South Vietnam and show that artemisinin sensitivity does not differ before and after drug treatment. There was an increase in the level of mefloquine resistance in the isolates after drug treatment that was concomitant with a decrease in chloroquine resistance, suggesting that treatment with artemisinin has selected for increased mefloquine resistance. Mutations in the gene, previously shown to be associated with sensitivity to mefloquine, were selected against. All isolates resistant to chloroquine encoded Thr-76 in the gene consistent with an essential role in the mechanism of chloroquine resistance. Mutations in also were linked to chloroquine resistance. High levels of mutation in and genes, which have previously been associated with Fansidar resistance, also were found, suggesting that this drug would not be useful for malaria control in this part of Vietnam.


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  • Received : 02 May 2002
  • Accepted : 07 Oct 2002

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