ArticleMalaria journal2019
High prevalence of Pfdhfr-Pfdhps quadruple mutations associated with sulfadoxine-pyrimethamine resistance in Plasmodium falciparum isolates from Bioko Island, Equatorial Guinea.
Article in Malaria journal, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT04844099 (Dihydroartemisinin-Piperaquine or Sulphadoxine-Pyrimethamine for the Chemoprevention of Malaria in Children With Sickle Cell Anaemia in Eastern and Southern Africa), which is not on this map. Cited by 30 papers, 1 of them a synthesis that pooled it.
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Dihydroartemisinin-Piperaquine or Sulphadoxine-Pyrimethamine for the Chemoprevention of Malaria in Children With Sickle Cell Anaemia in Eastern and Southern Africa: a Double Blind Randomised Trial (CHEMCHA)
Who cites it
30 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Drug resistance markers within an evolving efficacy of anti-malarial drugs in Cameroon: a systematic review and meta-analysis (1998-2020).Malaria journal · 2021Pooled it
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- Polymorphism of the dihydropteroate synthase resistance gene of Plasmodium falciparum in three hospitals in Mbouda, Western Cameroon.Tropical diseases, travel medicine and vaccines · 2025Article
- Tracking Plasmodium falciparum antimalarial resistance markers during a malaria pre-elimination period in the Pacific coast of South America.Scientific reports · 2025Article
- Malaria: past, present, and future.Signal transduction and targeted therapy · 2025Review
- Exploring Genetic Silencing: RNAi and CRISPR-Cas Potential against Drug Resistance in Malaria.Mini reviews in medicinal chemistry · 2025Review
- Sub-microscopic Plasmodium falciparum infections and multiple drug resistant single nucleotide polymorphic alleles in pregnant women from southwestern Nigeria.BMC research notes · 2024Article
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- Plasmodium falciparum drug resistance-associated mutations in isolates from children living in endemic areas of Burkina Faso.Malaria journal · 2023Article
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- A snapshot of the prevalence of dihydropteroate synthase-431V mutation and other sulfadoxine-pyrimethamine resistance markers in Plasmodium falciparum isolates in Nigeria.Malaria journal · 2023Article
- Molecular surveillance of anti-malarial drug resistance genes in Plasmodium falciparum isolates in Odisha, India.Malaria journal · 2022Article
- Global Analysis ofMolecules (Basel, Switzerland) · 2022Article
- Molecular Determinants of Sulfadoxine-Pyrimethamine Resistance in Plasmodium falciparum Isolates from Central Africa between 2016 and 2021: Wide Geographic Spread of Highly MutatedMicrobiology spectrum · 2022Article
- Molecular Markers for Sulfadoxine/Pyrimethamine and Chloroquine Resistance in Plasmodium falciparum in Thailand.The Korean journal of parasitology · 2022Article
- Distinct pattern and prevalence ofThe Pan African medical journal · 2022Article
- Multiple Single-Nucleotide Polymorphism Detection for Antimalarial Pyrimethamine Resistance via Allele-Specific PCR Coupled with Gold Nanoparticle-Based Lateral Flow Biosensor.Antimicrobial agents and chemotherapy · 2021Article
- High Frequency Mutations inFrontiers in cellular and infection microbiology · 2021Article
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- Chloroquine and Sulfadoxine-Pyrimethamine Resistance in Sub-Saharan Africa-A Review.Frontiers in genetics · 2021Review
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Authors and funding
12 authors.
Funding
Abstract
backgroundSulfadoxine-pyrimethamine (SP) is recommended for intermittent preventive treatment of malaria in Africa. However, increasing SP resistance (SPR) affects the therapeutic efficacy of the SP. As molecular markers, Pfdhfr (dihydrofolate reductase) and Pfdhps (dihydropteroate synthase) genes are widely used for SPR surveillance. This study aimed to assess the prevalence of Pfdhfr and Pfdhps genes mutations and haplotypes in Plasmodium falciparum isolates collected from Bioko Island, Equatorial Guinea (EG).
methodsIn total, 180 samples were collected in 2013-2014. The single nucleotide polymorphisms (SNPs) of the Pfdhfr and Pfdhps genes were identified with nested PCR and Sanger sequencing. The genotypes and linkage disequilibrium (LD) tests were also analysed.
resultsSequences of Pfdhfr and Pfdhps genes were obtained from 92.78% (167/180) and 87.78% (158/180) of the samples, respectively. For Pfdhfr, 97.60% (163/167), 87.43% (146/167) and 97.01% (162/167) of the samples carried N51I, C59R and S108N mutant alleles, respectively. The prevalence of the Pfdhps S436A, A437G, K540E, A581G, and A613S mutations were observed in 20.25% (32/158), 90.51% (143/158), 5.06% (8/158), 0.63% (1/158), and 3.16% (5/158) of the samples, respectively. In total, 3 unique haplotypes at the Pfdhfr locus and 8 haplotypes at the Pfdhps locus were identified. A triple mutation (CIRNI) in Pfdhfr was the most prevalent haplotype (86.83%), and a single mutant haplotype (SGKAA; 62.66%) was predominant in Pfdhps. A total of 130 isolates with 12 unique haplotypes were found in the Pfdhfr and Pfdhps combined haplotypes, 65.38% (85/130) of them carried quadruple allele combinations (CIRNI-SGKAA), whereas only one isolate (0.77%, 1/130) was found to carry the wild-type (CNCSI-SAKAA). For LD analysis, the Pfdhfr N51I was significantly associated with the Pfdhps A437G (P < 0.05).
conclusionBioko Island possesses a high prevalence of the Pfdhfr triple mutation (CIRNI) and Pfdhps single mutation (SGKAA), which will undermine the pharmaceutical effect of SP for malaria treatment strategies. To avoid an increase in SPR, continuous molecular monitoring and additional control efforts are urgently needed in Bioko Island, Equatorial Guinea.
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