부산대학교 도서관

Background Malaria rapid diagnostic tests (RDTs) play a key role in malaria management and control. The PfHRP-2 based RDT is the most widely used RDT for malaria diagnosis in Ghana. Deletion of pfhrp 2 in Plasmodium falciparum parasites affect the diagnostic accuracy of PfHRP-2 based RDT kits. Identifying the prevalence and distribution of P. falciparum parasites with deleted pfhrp 2 is important for malaria control. Aim The purpose of this study was to identify and confirm the prevalence of pfhrp 2 deletant P. falciparu m parasites circulating within different regions of Ghana. Methods DNA was extracted from the membrane of spent CareStart⢠PfHRP-2 RDT kits and dried filter paper blood blots using Chelex-100. Exon 2 of pfhrp 2 and pfhrp 3 genes were amplified by polymerase chain reaction (PCR), resolved by agarose gel electrophoresis and visualized under UV light. Results Microscopic analysis of blood smears from samples that were PfHRP-2 RDT positive revealed a parasite prevalence of 54/114 (47.4 %) and 2/26 (7.7 %) in Accra and Cape Coast, respectively. PCR analysis increased parasite prevalence in the RDT positive samples to 94/114 (82.5 %) and 6/26 (23.1 %) in Accra and Cape Coast respectively. The exon 2 of the pfhrp 2 gene was deleted in 18/54 (33.3 %) of the microscopy confirmed and 36.2 % (34/94) of the PCR confirmed RDT positive samples collected in Accra. No RDT sample, confirmed to contain parasites by either PCR or microscopy was negative by pfhrp 2 exon 2 PCR in Cape Coast. A survey of an additional 558 DBS revealed that 22.4 % (46/205) and 40 % (44/110) of PCR positive samples in Accra and Cape Coast, respectively, lacked the exon 2 region of pfhrp 2 and possibly the entire pfhrp 2 gene. Conclusions A high number of P. falciparum parasites, which lack pfhrp 2 exon 2 gene have been identified in two communities in Ghana. Continuous nationwide monitoring of the prevalence of pfhrp 2 deletant parasites would be essential to malaria control. The use of RDT kits that are effective at malaria diagnosis despite deletion of pfhrp 2, such as the PfHRP-2/PfLDH combo RDT kit could enhance the diagnosis of clinical malaria in Ghana. Keywords: Malaria diagnosis, Plasmodium falciparum , Rapid diagnostic test (RDT), Plasmodium falciparum histidine rich protein-2 (PfHRP-2), Plasmodium falciparum histidine rich protein-3 gene (pfhrp 3)
Author(s): Linda Eva Amoah[sup.1] , Joana Abankwa[sup.1] and Akua Oppong[sup.1] Background Malaria is one of the deadliest infectious diseases of humanity, which causes significant mortality and morbidity in the tropics, [...]