Use of proscribed chloroquine is associated with an increased risk ofpfcrtT76 mutation in some parts of Ghana

Abstract

Background: After years of disuse of chloroquine (CQ) as first-line anti-malarial drug in Ghana, reports from molecular studies conducted in parts of the country indicate varying prevalence of 76 mutation in the pfcrtgene. This situation has several health implications, one being that mutations that confer resistance to CQ have been reported to show substantial cross-resistance to other anti-malarial drugs. It is important to identify some of the factors contributing to the continuous presence of CQ resistance markers in the country. This study determined the prevalence of 76 mutations in pfcrtgene of Plasmodium falciparum isolates collected from selected areas of the Central region of Ghana and correlated with the level of CQ use in these areas. Methods: Plasmodium falciparum DNA was extracted from collected blood-blot filter paper samples in the study sites. The prevalence of 76 point mutation in pfcrtgene was assessed using nested PCR followed by RFLP. CQ from pharmacy and chemical shops was obtained using mystery buying method. he extent of CQ use by the participants was determined by measuring the level of the drug in their urine samples using the Saker-Solomon method. Results: Of the 214 P. falciparum isolates analyzed, 71.9% were found to have 76 mutation of pfcrtgene. The study revealed that 14.49% of community pharmacies and chemical shops had stocks of CQ for sale while 16.9% of the participants had CQ in their urine samples. here is five times more risks of becoming infected with CQ resistant strain for staying in an area where CQ is stocked for sale [RR = 0.20, p < 0.0001] and thirteen times more risks of having CQ-resistant mutant from those who still use CQ than non-users [OR = 0.08, p < 0.0001]. Conclusion: This study has shown that high variation in the prevalence of 76 mutations of P. falciparum is linked with the level of CQ stocking and usage within study area