Antimalarial drug resistance monitoring is the key factor in malaria control policy for early detection and subsequent prevention of drug resistance spread. This review was performed to collate all available data of P. falciparum resistant genes in the Horn of Africa as a baseline for future appraisal of the regional malaria control policy. The search of this review was performed in January 2018 using the scientific databases Pub Med and Google Scholar. The search terms used included: Plasmodium falciparum AND drug resistance genes OR molecular marks AND Somalia OR Ethiopia OR Eritrea OR Djibouti. The majority of studies (9 of 18 studies, 50%) examined pfdhfr, pfcrt and pfmdr 1 genes. Eight (44%), 4 (22%), and 2 (11%) studies analyzed pfdhps, pfk 13 and pfatp 6 genes, respectively. The Pfcytbc1 associated with atovaquone resistance is the only gene with no mutation detected. High frequencies of pfdhfr and pfdhps mutations were reported with an association to treatment failure after the artemisinin-based combination therapy (ACT) -artesunate + sulfadoxine/pyrimethamine. The aminoquinoline resistance genes such as pfmdr1, and pfatp 6 were only reported with low frequency. The 76T mutation of pfcrt ranged from 4 to 100%, while pfmdr1 mutations at codon 86 and 184 varied depending on geographical locations. The 402V and 431K mutations of pfatp 6 were found highly prevalent at 93 % and 58 % in Southwestern Ethiopia, respectively. The pfk13 gene mutation at codon 622I was 2.4%, with an association to artemether-lumefantrine efficacy and delay of parasite clearance on day 3.
The use of an effective antimalarial drug is the cornerstone of malaria control. However, the development and spread of resistant <i>Plasmodium falciparum</i> strains have placed the global eradication of malaria in serious jeopardy. Molecular marker analysis constitutes the hallmark of the monitoring of <i>Plasmodium</i> drug-resistance. This study included 96 <i>P. falciparum</i> PCR-positive samples from southern Somalia. The <i>P. falciparum chloroquine resistance transporter</i> gene had high frequencies of K76T, A220S, Q271E, N326S, and R371I point mutations. The N86Y and Y184F mutant alleles of the <i>P. falciparum multidrug resistance 1</i> gene were present in 84.7 and 62.4% of the isolates, respectively. No mutation was found in the <i>P. falciparum Kelch-13</i> gene. This study revealed that chloroquine resistance markers are present at high frequencies, while the parasite remains sensitive to artemisinin (ART). The continuous monitoring of ART-resistant markers and in vitro susceptibility testing are strongly recommended to track resistant strains in real time.
High levels of genetic variants of Plasmodium vivax have previously been reported in Thailand. Circumsporozoite surface protein (CSP), merozoite surface protein (MSP), and microsatellite markers were used to determine the genetic polymorphisms of P. vivax. This study aimed to investigate the molecular epidemiology of P. vivax populations at the Thai–Myanmar border by genotyping the PvCSP, PvMSP-3α, and PvMSP-3β genes. Four hundred and forty P. vivax clinical isolates were collected from the Mae Sot and Sai Yok districts from 2006–2007 and 2014–2016. Polymerase chain reaction with restriction fragment length polymorphism (RFLP) was used to investigate the genetic polymorphisms of the target genes. Based on PCR band size variations, 14 different PvCSP alleles were identified: eight for VK210 and six for VK247. The VK210 genotype was the dominant variant during both sample collection periods. Based on PCR genotyping, three distinct types (A, B, and C) for both PvMSP-3α and PvMSP-3β were observed. Following RFLP, 28 and 14 allelic variants of PvMSP-3α and 36 and 20 allelic variants of PvMSP-3β with varying frequencies were identified during the first and second periods, respectively. High genetic variants of PvMSP-3 and PvCSP were found in the study area. PvMSP-3β exhibited a higher level of genetic diversity and multiple-genotype infection versus PvMSP-3α.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.