Drug-Resistant Polymorphisms and Copy Numbers in Plasmodium falciparum, Mozambique, 2015

Emerg Infect Dis. 2018 Jan;24(1):40-48. doi: 10.3201/eid2401.170864.

Abstract

One of the fundamental steps toward malaria control is the use of antimalarial drugs. The success of antimalarial treatment can be affected by the presence of drug-resistant populations of Plasmodium falciparum. To assess resistance, we used molecular methods to examine 351 P. falciparum isolates collected from 4 sentinel sites in Mozambique for K13, pfmdr1, pfcrt, and pfdhps polymorphisms and for plasmepsin2 (pfpm2) and pfmdr1 copy numbers. We found multiple copies of pfpm2 in 1.1% of isolates. All isolates carried K13 wild-type alleles (3D7-like), except 4 novel polymorphisms (Leu619Leu, Phe656Ile, Val666Val, Gly690Gly). Prevalence of isolates with pfcrt mutant (K76T) allele was low (2.3%). Prevalence of isolates with pfdhps mutant alleles (A437G and K540E) was >80%, indicating persistence of sulfadoxine/pyrimethamine resistance; however, markers of artemisinin were absent, and markers of piperaquine resistance were low. Piperaquine resistance isolates may spread in Mozambique as dihydroartemisinin/piperaquine drug pressure increases.

Keywords: K13; Mozambique; antimicrobial resistance; copy number; malaria; parasites; plasmepsin2; polymorphisms; vector-borne infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Antimalarials / pharmacology
  • DNA Copy Number Variations / genetics
  • Drug Resistance / genetics
  • Humans
  • Malaria, Falciparum / drug therapy
  • Malaria, Falciparum / epidemiology
  • Malaria, Falciparum / parasitology
  • Mozambique
  • Plasmodium falciparum / drug effects*
  • Plasmodium falciparum / genetics
  • Polymorphism, Genetic / genetics

Substances

  • Antimalarials