Evaluation of Plasmodium falciparum chloroquine resistant markers in selected health facilities in the Central Region after seven years of banning chloroquine treatment in Ghana

Abstract

The continuous Chloroquine (CQ) use resulted in intensified parasite resistance to CQ. This led to adaptation of artemisinin based combination therapy (ACT) as the first-line antimalarial drug for the treatment of uncomplicated malaria in January, 2005. Despite the replacement, anecdotal evidences suggest that CQ is still being used in many communities in Ghana. This study was conducted to investigate the continuous use of CQ and its effect on CQ resistance markers in the Central Region, Ghana. Using questionnaire, mystery buying and Sakar-Solomon’s urine CQ assay method, a survey was conducted to ascertain the continuous use of CQ. The prevalence of point mutations of Pfcrt and Pfmdr1 genes were assessed from Plasmodium falciparum infected blood samples of subjects, employing the nested PCR and RFLP techniques. Out of 618 subjects, 2.43% of the subjects preferred to use CQ injection while 0.49% confirmed the use CQ for treatment of malaria. Out of 69 community pharmacies and chemical shops surveyed, 14.49% had stocks of CQ which were being dispensed. Qualitative urine assay revealed that 16.9% out of 444 participants had CQ in their urine samples. Of the 214 P. falciparum isolates, 71.9% were found to have the K76T mutation of Pfcrt. The risk of becoming infected with CQ resistant P. falciparum strain with mutation at position 76 of pfcrt in people who had chloroquine in their urine was thirteen times [OR=12.63, 95%CI (8.57-18.62)], p<0.0001. Those who stay at communities where community pharmacies or chemical shops stocks chloroquine are five times more likely to become infected with CQ resistant P. falciparum strain, with mutation at position 76 of pfcrt [RR=4.97, 95%CI (2.97-8.86)], p<0.0001. In conclusion the prevalence of chloroquine resistance markers have remained high in the country due to continuous chloroquine use.