Increased prevalence of pfdhfr and pfdhps mutations associated with sulfadoxine–pyrimethamine resistance in Plasmodium falciparum isolates from Jazan Region, Southwestern Saudi Arabia: important implications for malaria treatment policy

Abstract

Background Despite significant progress in eliminating malaria from the Kingdom of Saudi Arabia, the disease is still endemic in the southwestern region of the country. Artesunate plus sulfadoxine–pyrimethamine (AS + SP) has been used in Saudi Arabia since 2007 as a first-line treatment for uncomplicated Plasmodium falciparum malaria. This study aimed to investigate the prevalence of mutations associated with resistance to artemisinin and sulfadoxine–pyrimethamine (SP) resistance in P. falciparum parasites circulating in Jazan region, southwestern Saudi Arabia. Methods A total of 151 P. falciparum isolates were collected between April 2018 and March 2019 from 12 of the governorates in Jazan region. Genomic DNA was extracted from dried blood spots and amplified using nested PCR. Polymorphisms in the propeller domain of the P. falciparum k13 (pfkelch13) gene and point mutations in the P. falciparum dihydrofolate reductase (pfdhfr) and dihydropteroate synthase (pfdhps) genes were identified by sequencing. Results No mutations in the pfkelch13 propeller domain were found in any of the 151 isolates. However, point mutations in the pfdhfr and pfdhps genes were detected in 90.7% (137/151) of the isolates. The pfdhfr double mutations N51I + S108N (i.e. ACICNI haplotype) and triple mutations N51I + C59R + S108N (i.e. ACIRNI haplotype) were detected in 47% and 37.8% of the isolates, respectively. Moreover, the pfdhps single mutation at codon A437G and double mutations A437G + K540E (i.e. SGEAAI haplotype) were observed in 4.6% and 51.7% of the isolates, respectively. Interestingly, 23.8%, 25.1 and 12.6% of the isolates had quintuple, quadruple and triple mutated combined pfdhfr–pfdhps genotypes, respectively. Furthermore, significant associations were found between the prevalence of mutant haplotypes and the age, gender and nationality of the patients (P < 0.05). Conclusion This study revealed a high prevalence of point mutations in the pfdhfr and pfdhps genes of P. falciparum isolates from Jazan region, with quintuple and quadruple mutant pfdhfr–pfdhps genotypes reported for the first time in Saudi Arabia and the Arabian Peninsula. Despite the absence of the pfkelch13 mutation in the isolates examined, the pfdhfr and pfdhps mutations undermine the efficacy of SP partner drug, thereby threatening the main falciparum malaria treatment policy in Saudi Arabia, i.e. the use of AS + SP. Therefore, the continuous molecular and in-vivo monitoring of ACT efficacy in Jazan region is highly recommended.

Residual malaria in Jazan region, southwestern Saudi Arabia: the situation, challenges and climatic drivers of autochthonous malaria

“…Hence, it seems that, unless there are appropriate measures in place, the construction of dams for irrigation and hydroelectric generation could intensify malaria transmission by providing breeding habitats for prominent malaria vector species, especially in areas of unstable or limited transmission [ 18 , 39 ]. In addition, increased cross-border importation of malaria [ 34 ] and poor awareness of malaria prevention measures among the general population [ 40 ], as well as the emerging resistance of the parasites to treatment and the resistance of the vectors to insecticides might also have contributed to this outbreak [ 19 ]. Therefore, this malaria outbreak indicates that there is a need for rigorous impact assessments of metrological and climate change-related variables as well as dam-related environmental factors in Jazan region.…”

“…stephensi , An . superpictus , and Anopheles culicifacies [ 18 , 19 ]. Although mosquitoes can be found throughout the year, the presence of Anopheles usually peaks following the rainy season that falls during October to December [ 20 , 21 ].…”

Current Epidemiological Characteristics of Imported Malaria, Vector Control Status and Malaria Elimination Prospects in the Gulf Cooperation Council (GCC) Countries

“…Another study carried out in the Jazan region, southwestern Saudi Arabia, where artesunate plus sulfadoxine/pyrimethamine has been used since 2007 as a first-line treatment for uncomplicated P. falciparum malaria, investigated the prevalence of mutations associated with artemisinin and sulfadoxine/pyrimethamine resistance in the parasites circulating in this region. Polymorphisms in the propeller domain of the P. falciparum k13 (pfkelch13) gene and point mutations in the pfdhfr and pfdhps genes were identified by DNA sequencing [ 63 ]. Although no mutations were found in any of the 151 isolates in the pfkelch13 propeller domain, point mutations in pfdhfr and pfdhps genes were detected in 90.7% (137/151) of the isolates including double (N51I + S108N) and triple (N51I + C59R + S108N) pfdhfr mutations.…”

“…Although drug resistance-conferring pfkelch13 mutations were not found, mutations in the pfdhfr and pfdhps genes were detected. The authors concluded that their observations undermine the efficacy of artemisinin-based combination therapy in the Jazan region in Saudi Arabia [ 63 ].…”

The return of chloroquine-sensitive Plasmodium falciparum parasites in Jazan Region, Southwestern Saudi Arabia over a decade after the adoption of artemisinin-based combination therapy: analysis of genetic mutations in the pfcrt gene

“…In Saudi Arabia, CQ resistance was rst recorded in 1992 when reports on clinical treatment failures increased (Malik et al 1997;Alrajhi et al 1999;Al Arishi et al 2001). Subsequently, the malaria drug policy in the country was scaled up in 2007 and CQ was replaced with ACT, with artesunate plus SP as a rst-line treatment and artemether-lumefanthrine as the second-line for the treatment of uncomplicated falciparum malaria (Madkhali et al 2020;MOH 2018). Since then, some molecular studies have revealed a high prevalence of pfcrt 76T mutations in isolates from different areas of the country (Al Harthi, 2007; Bin Dajem and Al-Qahtani 2010; Bin Dajem et al 2012).…”