Malaria Journal (Aug 2011)

Molecular markers of antifolate resistance in <it>Plasmodium falciparum </it>isolates from Luanda, Angola

  • Almeida de Oliveira Natália K,
  • Lutucuta Kosi Florbela JI,
  • Pereira-Carvalho Guilhermina AL,
  • Gama Bianca E,
  • Fortes Filomeno,
  • Rosenthal Philip J,
  • do Rosário Virgílio E,
  • Daniel-Ribeiro Cláudio,
  • Fátima Ferreira-da-Cruz Maria

DOI
https://doi.org/10.1186/1475-2875-10-248
Journal volume & issue
Vol. 10, no. 1
p. 248

Abstract

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Abstract Background Plasmodium falciparum malaria remains a leading health problem in Africa and its control is seriously challenged by drug resistance. Although resistance to the sulphadoxine-pyrimethamine (SP) is widespread, this combination remains an important component of malaria control programmes as intermittent preventive therapy (IPT) for pregnant women and children. In Angola, resistance patterns have been poorly characterized, and IPT has been employed for pregnant women since 2006. The aim of this study was to assess the prevalence of key antifolate resistance mediating polymorphisms in the pfdhfr and pfdhps genes in P. falciparum samples from Angola. Methods Plasmodium falciparum samples collected in Luanda, in 2007, were genotyped by amplification and DNA forward and reverse sequencing of the pfdhfr and pfdhps genes. Results The most prevalent polymorphisms identified were pfdhfr 108N (100%), 51I (93%), 59R (57%) and pfdhps 437G (93%). Resistance-mediating polymorphisms in pfdhps less commonly observed in West Africa were also identified (540E in 10%, 581G in 7% of samples). Conclusion This study documents an important prevalence of 4 P. falciparum polymorphisms that predicts an antifolate resistance in Luanda. Further, some samples presented additional mutations associated to high-level resistance. These results suggest that the use of SP for IPT may no longer be warranted in Angola.