MOLECULAR IDENTIFICATION OF PLASMODIUM FALCIPARUM ISOLATES IN OWERRI MUNICIPALITY USING NESTED POLYMERASE CHAIN REACTION (NPCR)

As Public health seek ways to annihilate malaria, there has been special attention to abrogate low-density parasite reservoirs in carriers. This research was designed to detect Plasmodium falciparum using nested polymerase chain reaction (nPCR) as a diagnostic tool to test for malaria prevalence in Owerri municipality, and the result compared to that of microscopy. A total of 300 blood samples were collected from febrile patients who sought treatment from selected hospitals in Owerri municipal. Microscopy was carried out on Giemsa-stained blood smears of the samples. Extraction of Plasmodium falciparum DNA from the blood samples was carried out, and the DNA products were analyzed using nPCR with genus and specie specific primers in a two-step amplification of the Pfmdr gene. The PCR products were analyzed in ethidium bromide stained 2% agarose gel. The result from microscopy showed that 130(43.3%) samples were P. falciparum positive and 170(56.7%) samples were negative, while that of nPCR, showed 202(67.3%) samples were positive and 98(32.7%) samples were negative. Out of the 170 samples that were microscopically examined as negative, 72(42.35%) were positive with nPCR. This indicates that there is high level of false negative result by microscopy, which may either lead to negation for a deserved treatment or undeserved treatment. Accurate diagnosis of Plasmodium falciparum is of importance in the treatment of malaria. Microscopic examination of blood smears remains the "gold standard" for malaria detection and speciation. In spite of the fact that there is significant drop in the number of positive cases reported from microscopy, antimalarial drugs prescriptions are on the rise as patients exhibit symptoms of malaria. This makes it tough to confirm accuracy, sensitivity and specificity of light microscopy in diagnosis of malaria in epidemic areas. Polymerase chain reaction offers an alternative to microscopy having shown to have superior sensitivity and specificity. Diagnosis of malaria parasites by nPCR will serve as a useful complement to microscopy, albeit it's high cost and time consumption. In addition, negative patients suspected to have malaria should be subjected to PCR diagnosis to better drug use.