Molecular monitoring of Plasmodium falciparum resistance to antimalarial drugs after adoption of sulfadoxine-pyrimethamine plus artesunate as the first line treatment in Iran

► Whether the therapy of SP plus AS protects against the spread of resistance to SP. ► pfdhps, pfdhfr, pfcrt and pfmdr1 were analyzed in 170 Plasmodium falciparum samples. ► The prevalence of pfdhfr/pfdhps triple mutations decreased from 53.3% in 2008 to 38% in 2010. ► SP is effective for treatment of uncomplicated falciparum malaria in Iran.