Gametocyte Carriage, Antimalarial Use, and Drug Resistance in Cambodia, 2008-2014

Am J Trop Med Hyg. 2018 Nov;99(5):1145-1149. doi: 10.4269/ajtmh.18-0509.

Abstract

Gametocytes are the malaria parasite stages responsible for transmission from humans to mosquitoes. Gametocytemia often follows drug treatment, especially as therapies start to fail. We examined Plasmodium falciparum gametocyte carriage and drug resistance profiles among 824 persons with uncomplicated malaria in Cambodia to determine whether prevalent drug resistance and antimalarial use has led to a concentration of drug-resistant parasites among gametocyte carriers. Although report of prior antimalarial use increased from 2008 to 2014, the prevalence of study participants presenting with microscopic gametocyte carriage declined. Gametocytemia was more common in those reporting antimalarial use within the past year, and prior antimalarial use was correlated with higher IC50s to piperaquine and mefloquine, as well as to increased pfmdr1 copy number. However, there was no association between microscopic gametocyte carriage and parasite drug resistance. Thus, we found no evidence that the infectious reservoir, marked by those carrying gametocytes, is enriched with drug-resistant parasites.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Antimalarials / pharmacology*
  • Artemisinins / therapeutic use
  • Cambodia / epidemiology
  • Drug Resistance, Multiple*
  • Female
  • Humans
  • Inhibitory Concentration 50
  • Malaria, Falciparum / blood*
  • Malaria, Falciparum / drug therapy*
  • Malaria, Falciparum / epidemiology
  • Male
  • Mefloquine / therapeutic use
  • Multidrug Resistance-Associated Proteins / economics
  • Plasmodium falciparum / drug effects*
  • Plasmodium falciparum / genetics
  • Young Adult

Substances

  • Antimalarials
  • Artemisinins
  • Mdr1 protein, Plasmodium falciparum
  • Multidrug Resistance-Associated Proteins
  • Mefloquine