IN VITRO ANTIMALARIAL SUSCEPTIBILITY OF PLASMODIUM FALCIPARUM ISOLATES FROM PATIENTS ATTENDING A HEALTH FACILITY IN WUSASA, ZARIA, NIGERIA

IN VITRO ANTIMALARIAL SUSCEPTIBILITY OF PLASMODIUM FALCIPARUM ISOLATES FROM PATIENTS ATTENDING A HEALTH FACILITY IN WUSASA, ZARIA, NIGERIA

Abstract:

The continous emergence and spread of resistant strains of Plasmodium falciparumisolates to single and combined antimalarial drug has resulted to increase in mortality rate associated with the disease, especially in the African Continent as a whole and Nigeria in particular where the disease continues to be endemic. In vitroantimalarial susceptibility of Plasmodiumfalciparumisolates from patients attending a Health facility in Wusasa, Zaria, Nigeria was carried out using WHO standard Mark III Micro- Test System. A retrospective study determined the incidence of malaria and pattern of antimalarial prescription at the Health Facility. A total of 953 people, comprising of 448 males (47%) and 505 females (53%) were reported to be infected with malaria from 2012 through 2014 in a Health facility in Wusasa, Zaria. Of this total number of reported cases, 265 (28%) were children between the ages of 0-5 years, 503(53%) were between the ages of 6-39 years and 185 (19%) were aged 40 and above. The incidence of malaria at the Health Facility, overthe three year period (2012-2014) was calculated to be 2.8%. Chloroquine, Quinine, Fansider/ Falcidine(Sulphadoxine+Pyrimethamine),Artemether, Artesunate, Coartem (Artemether+Lumefantrine), ASAQ (Artemether+Piperaquine), were the antimalarials that were routinely prescribed at a Health facility in Wusasa, Zaria from 2012 through 2014. Chloroquine was the most prescribed in year 2012(35.1%) and 2013(35.9%), While Coartem was the most prescribed in 2014(31.7%). A total of 120 blood samples of patients with Plasmodium falciparum malaria wereused in this study. However, only 30 samples were successfully evaluated, the remaining were not used due to patients admitting to taking antimalarial drugs 14 days prior to presentation, low parasite density, Failure of schizont to mature satisfactorily in the control well and contamination. Out of the total of 30 isolates of Plasmodium falciparum used in this study, comprising of 17 females and 13 males,8 were between the ages of 0-5, 14 were between the ages of 6-39 years and 8 were 40 and above. Most of the isolates (90%)were resistant to Quinine and Chloroquine, with median IC50 of 7.8μg/ml and 5.3μg/ml respectively. There was however 100% invitrosensitivity to Artemeter and Artemeter – lumefantrine combination. The crude extract of Psidium guajava and Carica papayashowed good antiplasmodial activity against Plasmodium falciparum isolates in the study conducted, with Median IC50 values of 9.2μg/ml and 5.4μg/ml respectively.Ten (10) of the resistant Plasmodium falciparum isolates were assayed to determine the prevalence of two of the established antimalarial drug resistance markers: the Chloroquine resistance transporter gene (pfcrt)and the multi-drug resistance transporter 1gene (pfmdr1). All 10 (100%) of the in vitroresistant isolates harboured the pfcrt chloroquine resistance gene, while 8(80%) harboured the pfmdr1gene. Theresult from this study shows that high level of chloroquine resistance still remains in this region and there is an alarming emergence of resistance to Quinine. Artemether and artemisin based combinations still remain very potent in treating malaria based on the in vitro results from this study. Psidium guajava and Carica papaya leaf extracts showed promising activity against resistant Plasmodium falciparum isolates in this study, making them plants of choice to be considered for the development of newer antimalarials.

IN VITRO ANTIMALARIAL SUSCEPTIBILITY OF PLASMODIUM FALCIPARUM ISOLATES FROM PATIENTS ATTENDING A HEALTH FACILITY IN WUSASA, ZARIA, NIGERIA