Detection of mutations associated with artemisinin resistance at k13-propeller gene and a near complete return of chloroquine susceptible falciparum malaria in Southeast of Tanzania

Abstract

In Tanzania, chloroquine was replaced by sulphadoxine-pyrimethamine (SP) as a first-line for treatment of uncomplicated malaria. Due to high resistance in malaria parasites, SP lasted for only 5 years and by the end of 2006 it was replaced with the current artemisinin combination therapy. We therefore, set a study to determine the current genotypic mutations associated with Plasmodium falciparum resistance to artemisinin, partner drugs and chloroquine. parasites DnA were extracted from dried blood spots collected by finger-prick from Tanzanian malaria infected patients. DNA were sequenced using MiSeq then genotypes were translated into drug resistance haplotypes at Wellcome Sanger institute, UK. About 422 samples were successful sequenced for K13 gene (marker for artemisinin resistance), the wild type (WT) was found in 391 samples (92.7%) whereby 31 samples (7.3%) had mutations in K13 gene. Of 31 samples with mutations, one sample had R561H, a mutation that has been associated with delayed parasite clearance in Southeast Asia, another sample had A578S, a mutation not associated with artemisinin whilst 29 samples had K13 novel mutations. there were no mutations in PGB, EXO, P23_BP and PfMDR1 at position 86 and 1246 (markers for resistance in artemisinin partner drugs) but 270 samples (60.4%) had mutations at PfMDR1 Y184F. Additionally, genotyped PfCRT at positions 72-76 (major predictors for chroquine resistance), found WT gene in 443 out of 444 samples (99.8%). in conclusion, this study found mutations in K13-propeller gene and high prevalence of chloroquine susceptible P. falciparum in Southeast of tanzania. Artemisinin-based combination therapy (ACT) is recommended by World Health Organization (WHO) to its partner states 1,2 as the first and second-line treatment for uncomplicated Plasmodium falciparum malaria as well as chloroquine-resistant Plasmodium vivax 3. In Tanzania chloroquine (CQ) was replaced by sulphadoxinepyrimethamine (SP) as first-line treatment and amodiaquine as second-line for uncomplicated malaria, due to high resistance SP lasted for only five years and by the end of 2006 it was replaced with the current ACT 4. Reversibly, an extended use of artemisinin (ART)-based combination therapy in malaria control and elimination programs has resulted to an emergence of P. falciparum resistant to ART derivatives in Southeast Asia 5. The risk of ART-resistant parasites reported to spread from western Cambodia to the Greater Mekong Subregion and to Africa 6. This is an urgent concern for global health 7. The spread of resistant P. falciparum to previous first-line

The return of chloroquine susceptible Plasmodium falciparum in Sub-Saharan Africa: a protocol for systematic review

“…On the other hand, countries with restricted used of CQ observed CQ-susceptible P. falciparum parasites have reemerged and are now predominant (4,13,14,23). In contrary to this, high levels of CQ resistance have persisted in countries with unrestricted use of CQ, i.e., Nigeria (24).…”

Drug resistance markers within an evolving efficacy of anti-malarial drugs in Cameroon: a systematic review and meta-analysis protocol

“…Furthermore, high prevalence rates of Pfdhfr IRN and Pfdhfr/Pfdhps IRNG conferring resistance to the anti-folates have been recorded in Equatorial Guinea, a country bordering Cameroon [40,41]. In addition, the recent identi cation of the Pfk13 R561H gene polymorphisms in Tanzania [25] and Rwanda [26] should be of major concern to malaria endemic countries in sub-Saharan Africa including Cameroon. This is because the artemisinins either used singly or in combination with other drugs is the mainstay in the treatment of malaria globally.…”

Drug resistance markers within an evolving efficacy of anti-malarial drugs in Cameroon: a systematic review and meta-analysis protocol

“…Furthermore, high prevalence rates of Pfdhfr IRN and Pfdhfr/Pfdhps IRNG conferring resistance to the anti-folates have been recorded in Equatorial Guinea, a country bordering Cameroon [40,41]. In addition, the recent identi cation of the Pfk13 R561H gene polymorphisms in Tanzania [25] and Rwanda [26] should be of major concern to malaria endemic countries in sub-Saharan Africa including Cameroon. This is because the artemisinins either used singly or in combination with other drugs is the mainstay in the treatment of malaria globally.…”

“…A number of mutations have also been reported outside the K13 propeller region notably, K189T and E252Q [19,[21][22][23]. In Africa, the highest geographical distribution is A578S [18,19,24] and the presence of R561H mutation has recently been reported in Tanzania [25] and Rwanda [26]. Hence, there are fears that ACT resistance may spread to other regions including sub-Saharan Africa where malaria is still a major burden, similar to what happened in the past with the chloroquine, amodiaquine, and sulphadoxine-pyrimethamine.…”