Publications & Reports

Assessment of susceptibility of Plasmodium falciparum to chloroquine, quinine, mefloquine, sulfadoxine-pyrimethamine and artemisinin in southern Viet Nam.

Thanh NV, Cowman AF, Hipgrave D, Kim TB, Phuc BQ, Cong LD, Biggs BA
National Institute of Malariology, Parasitology and Entomology, Hanoi, Viet Nam.


Resistance to antimalarial chemotherapy is a major concern for malaria control in Viet Nam. In this study undertaken in 1998, 65 patients with uncomplicated Plasmodium falciparum malaria were monitored for 28 days after completion of a 5-day treatment course with artemisinin. Overall 36.9% (24/65) of patients had recurrent parasitaemia during the surveillance period. P. falciparum isolates were tested for sensitivity in vitro to chloroquine, mefloquine, quinine, sulfadoxine-pyrimethamine and results were compared to those from a similar study in 1995. Increased parasite sensitivity to sulfadoxine-pyrimethamine, chloroquine and quinine was demonstrated, with significantly lower mean EC50 and EC99 values in 1998 compared to 1995. Parasite sensitivity to mefloquine did not differ significantly in the 2 surveys. Isolates were also tested for sensitivity in vitro to artemisinin in the 1998 survey. The mean EC50 was 0.03 mumol/L and the EC99 was 0.94 mumol/L. Parasite sensitivity to artemisinin will need to be monitored in view of its increasing use in Viet Nam.


  • Journal: Transactions of the Royal Society of Tropical Medicine and Hygiene
  • Published: 01/09/2001
  • Volume: 95
  • Issue: 5
  • Pagination: 513-517

Health Issue