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Background: Thanks to the scale up of malaria control interventions, the malaria burden in Senegal has decreased substantially to the point that the National Malaria Control Programme plans to achieve malaria elimination by 2030. To guide such efforts, measuring and monitoring parasite population evolution and anti-malarial drugs resistance is extremely important. Information on the prevalence of parasite mutations related to drug resistance can provide a first signal of emergence, introduction and selection that can help with refining drug interventions. The aim of this study was to analyse the prevalence of anti-malarial drug resistance-associated markers before and after the implementation of artemisinin-based combination therapy (ACT) from 2005 to 2014 in Dielmo, a model site for malaria intervention studies in Senegal., Methods: Samples from both malaria patients and Plasmodium falciparum asymptomatic carriers were analysed with high resolution melting (HRM) technique to genotype P. falciparum chloroquine resistance transporter (Pfcrt) gene haplotypes and multidrug-resistant protein 1 (Pfmdr1) gene at codons N86 and Y184., Results: Among the 539 samples analysed, 474, 486, and 511 were successfully genotyped for Pfmdr1 N86, Y184, and Pfcrt, respectively. The prevalence of drug resistance markers was high, particularly during the malaria upsurges. Following the scale-up in bed net distribution, only the mutant (86F-like) variant of Pfmdr1 86 was present while during the malaria upsurges the predominance of two types 86Y-86N (43%) and 86F-like (56%) were observed. Most infections (87%) carried the wild type Y-allele at Pfmdr1 184 during the period of nets scale-up while during the malaria upsurges only 16% of infections had wild type and 79% of infections had mixed (mutant/wild) type. The frequency of the mixed genotypes SVMNT-like&#95;CVMNK and SVMNT-like&#95;CVIET within Pfcrt gene was particularly low during bednet scale up. Their frequency increased significantly (P < 0.001) during the malaria upsurges., Conclusion: This data demonstrated the effect of multiple interventions on the dynamics of drug resistance-associated mutations in the main malaria parasite P. falciparum in an endemic village in Senegal. Monitoring drug resistance markers should be conducted periodically to detect threats of emergence or resurgence that could compromise the efficacy of anti-malarial drugs., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: The development of resistance by Plasmodium falciparum to anti-malarial drugs impedes any benefits of the drug. In addition, absence or delayed availability of current anti-malarial drugs in remote areas has the potential to results to parasite escape and continuous transmission., Case Presentation: The case of a 29-year old pregnant woman from Biase Local Government Area in Cross River State Nigeria presenting with febrile illness and high body temperature of 38.7 °C was reported. She looked pale and vomited twice on arrival at the health facility. Her blood smear on the first day of hospitalization was positive for P. falciparum by RDT, microscopy (21,960 parasite/µl) and real-time PCR, with a PCV of 18%. She was treated with 600 mg intravenous quinine in 500 ml of 5% Dextrose/0.9% Saline 8-hourly for 24 h. On the second day of hospitalization, she complained of weakness, persistent high-grade fever and vaginal bleeding. A bulging amnion from an extended cervix was observed. Following venous blood collection for laboratory investigations, 600 µg of misoprostol was inserted into the posterior fornix of her vagina as part of her obstetric care. Parenteral quinine was discontinued, and she was given full therapeutic regimen of artemether-lumefantrine 80/480 mg tablets to be taken for 3 days beginning from the second day. Her blood samples on the second and third day of hospitalization remained positive for P. falciparum by all three diagnostic methods. Single nucleotide polymorphism (SNP) assay on all three P. falciparum isolates revealed the presence of variants associated with multiple drug resistant markers., Discussion: Infecting P. falciparum isolates may have been resistant to initial quinine treatment resulting from parasite cross-resistance with other quinoline associated resistant markers such as 86Y and 184 F., Conclusions: Therefore, the likely transmission of similarly resistant parasites in the study area calls for reinforcement of interventions and adherence to current World Health Organization guidelines in administering only approved drugs to individuals in order to mitigate parasite escape and eventual transmission to other susceptible individuals., (© 2022. The Author(s).)