Background Antimalarial drug resistance is a major drawback to malaria elimination agenda. In response to widespread chloroquine (CQ) failure, Nigeria’s Health Ministry outlawed the drug for uncomplicated malaria treatment in 2005. Several studies have consistently reported a reversal to CQ susceptibility by Plasmodium falciparum years after hiatus. However, non-adherence to treatment guidelines and anecdotal repurposing of CQ potentially encourage the persistence of drug pressure favoring the fitness of the mutant allele. In this study, we investigated the existing prevalence of a point mutation at position 76 associated with P. falciparum chloroquine resistance.

Methods Sixty-three P. falciparum isolates were collected from Oriokuta Health Centre, Ikorodu, Lagos, during the drug therapeutic efficacy assessments conducted in 2021. Deoxyribonucleic acid (DNA) was extracted and malaria positivity was confirmed by Pf 18S rRNA. Subsequently, the DNA samples were assayed by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP) to determine the prevalence of Pfcrt-K76T mutation.

Results RFLP analysis identified 39/63 (62%) wild-type K76 and 24/63 (38%) mutant 76T genotype.

Conclusion Our finding points to an evolving epidemiology of Pfcrt K76T alleles. There appears to be an indication of a potential decline in the frequency of 76T mutation. However, this requires further substantiation using advanced variant validation tools in a larger parasite population.