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Background   Plasmodium vivax  is the predominant species of human malaria parasites present in China. Although sulphadoxine-pyrimethamine (SP) and chloroquine (CQ) have been widely used for malaria treatment in China, the resistance profiles of these drugs are not available. Analysis of dihydrofolate reductase ( dhfr ), dihydropteroate synthase ( dhps ), and multidrug resistance ( mdr-1 ) gene mutations in  P. vivax  isolates is a valuable molecular approach for mapping resistance to SP and CQ. This study investigates the prevalence of  pvdhfr ,  pvdhps , and  pvmdr-1  of  P. vivax  clinical isolates from China and provides baseline molecular epidemiologic data on SP- and CQ-associated resistance in  P. vivax .    Methods   Plasmodium vivax  clinical isolates were collected from two malaria-endemic regions of China, subtropical (Xishuangbanna, Yunnan province) and temperate (Bozhou, Anhui province), from 2009 to 2012. All isolates were analysed for single nucleotide polymorphism haplotypes in  pvdhfr ,  pvdhps,  and  pvmdr-1  using direct DNA sequencing.    Results  In  pvdhfr , 15% of Xishuangbanna isolates carried wild-type (WT) allele, whereas the majority of isolates carried mutant genes with substitutions at five codons. Eight mutant haplotypes of  pvdhfr  were detected, while limited polymorphism of  pvdhfr  was found in Bozhou isolates. A size polymorphism was present in  pvdhfr,  with the three-repeat type being the most predominate in both Xishuangbanna (79%) and Bozhou (97%) isolates. In  pvdhps , mutations at four codons were detected in Xishuangbanna isolates leading to six haplotypes, including WT allele, single-mutation, double-mutation, and triple-mutation alleles. All Bozhou isolates carried WT  pvhdps . In  pvmdr-1 , isolates from Xishuangbanna carried mutations at codons Y976F and F1076L, whereas all isolates from Bozhou had only a single mutation at codon F1076L.    Conclusions   Plasmodium vivax  isolates from subtropical and temperate zones of China are shown to have dramatically different frequencies and patterns of mutations in  pvdhfr ,  pvdhps , and  pvmdr-1.  Whereas  P. vivax  populations in subtropical China are highly resistant to SP and CQ, those in the temperate zone may still be susceptible to SP and CQ. This information is useful for establishing treatment policy and provides a baseline for molecular surveillance of drug-resistant  P. vivax  in these areas.    Electronic supplementary material  The online version of this article (doi:10.1186/1475-2875-13-346) contains supplementary material, which is available to authorized users.

Molecular surveillance of pvdhfr, pvdhps, and pvmdr-1 mutations in Plasmodium vivax isolates from Yunnan and Anhui provinces of China