&lt;p&gt;Trends in Molecular Markers Associated with Resistance to Sulfadoxine-Pyrimethamine (SP) Among &lt;em&gt;Plasmodium falciparum&lt;/em&gt; Isolates on Bioko Island, Equatorial Guinea: 2011–2017&lt;/p&gt;

Lin, Liyun; Li, Jian; Huang, Huiying; Liang, Xueqing; Jiang, Tingting; Chen, Jiangtao; Ehapo, Carlos Salas; Eyi, Urbano Monsuy; Zheng, Yuzhong; Zha, Guang-Cai; Xie, Dong‐De; Wang, Yuling; Chen, Weizhong; Liu, Xiangzhi; Lin, Min

doi:10.2147/idr.s236898

Cited by 3 publications

(5 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be seen that the partially resistant (IRNG) and fully resistant (IRNGE) haplotypes have been progressively increasing since 1999, reaching their peak in 2019, whereas the super-resistant (IRNGEG) have always had a low trend over time, never exceeding 2% and not being found in 2019. The data obtained are consistent with previous studies with samples from the island of Bioko, where the partially and fully resistant types were the most common and the frequency of the super-resistant type was very low [ 57 ].…”

Section: Discussionsupporting

confidence: 91%

See 1 more Smart Citation

Temporal evolution of the resistance genotypes of Plasmodium falciparum in isolates from Equatorial Guinea during 20 years (1999 to 2019)

Berzosa

Fuente

Ta‐Tang

et al. 2021

Malar J

View full text Add to dashboard Cite

Background Malaria is one of the deadliest diseases in the world, particularly in Africa. As such, resistance to anti-malarial drugs is one of the most important problems in terms of global malaria control. This study assesses the evolution of the different resistance markers over time and the possible influence of interventions and treatment changes that have been made in Equatorial Guinea. Methods A total of 1223 biological samples obtained in the period 1999 to 2019 were included in the study. Screening for mutations in the pfdhfr, pfdhps, pfmdr1, and pfcrt genes was carried out by nested PCR and restriction-fragment length polymorphisms (RFLPs), and the study of pfk13 genes was carried out by nested PCR, followed by sequencing to determine the presence of mutations. Results The partially and fully resistant haplotypes (pfdhfr + pfdhps) were found to increase over time. Moreover, in 2019, the fully resistant haplotype was found to be increasing, although its super-resistant counterpart remains much less prevalent. A continued decline in pfmdr1 and pfcrt gene mutations over time was also found. The number of mutations detected in pfk13 has increased since 2008, when artemisinin-based combination therapy (ACT) were first introduced, with more mutations being observed in 2019, with two synonymous and five non-synonymous mutations being detected, although these are not related to resistance to ACT. In addition, the non-synonymous A578S mutation, which is the most frequent on the African continent, was detected in 2013, although not in the following years. Conclusions Withdrawal of the use of chloroquine (CQ) as a treatment in Equatorial Guinea has been shown to be effective over time, as wild-type parasite populations outnumber mutant populations. The upward trend observed in sulfadoxine-pyrimethamine (SP) resistance markers suggest its misuse, either alone or in combination with artesunate (AS) or amodiaquine (AQ), in some areas of the country, as was found in a previous study conducted by this group, which allows selective pressure from SP to continue. Single nucleotide polymorphisms (SNPs) 540E and 581G do not exceed the limit of 50 and 10%, respectively, thus meaning that SP is still effective as an intermittent preventive treatment (IPT) in this country. As for the pfk13 gene, no mutations have been detected in relation to resistance to ACT. However, in 2019 there is a greater accumulation of non-synonymous mutations compared to years prior to 2008. Graphical Abstract

show abstract

Section: Discussionsupporting

confidence: 91%

“…Current WHO recommendations suggest that SP-IPTp should be discontinued if the frequency of 540E exceeds 50% and that of 581G exceeds 10% [ 57 ]. Based on current evidence, IPTp and IPTi remain effective in preventing the adverse consequences of malaria on maternal, foetal and infant outcomes in Equatorial Guinea.…”

Section: Discussionmentioning

confidence: 99%

Temporal evolution of the resistance genotypes of Plasmodium falciparum in isolates from Equatorial Guinea during 20 years (1999 to 2019)

Berzosa

Fuente

Ta‐Tang

et al. 2021

Malar J

View full text Add to dashboard Cite

show abstract

“…It can be seen that the partially resistant (IRNG) and fully resistant (IRNGE) haplotypes have been progressively increasing since 1999, reaching their peak in 2019, whereas the super-resistant ones (IRNGEG) have always had a low trend over time, never exceeding 2% and not being found in 2019. The data obtained are consistent with previous studies with samples from the island of Bioko, where the partially and fully resistant types were the most common and the frequency of the super-resistant type was very low [57].…”

Section: Discussionsupporting

confidence: 91%

“…Although resistance-related haplotypes to SP exhibit an upward trend, it has been observed that mutations at positions 540E (36.6%) and 581G (1.4%) are not su ciently high to jeopardise the use of SP in IPT. Current WHO recommendations suggest that SP-IPTp should be discontinued if the frequency of 540E exceeds 50% and that of 581G exceeds 10% [57]. Based on current evidence, IPTp and IPTi remain effective in preventing the adverse consequences of malaria on maternal, foetal and infant outcomes in Equatorial Guinea.…”

Section: Discussionmentioning

confidence: 99%

Temporal Evolution of the Resistance Genotypes of Plasmodium Falciparum in Isolates From Equatorial Guinea During 20 Years (1999 to 2019).

Berzosa

Fuente

Ta‐Tang

et al. 2021

Preprint

View full text Add to dashboard Cite

Background: Malaria is one of the deadliest disease in the world, particularly in Africa. The resistance to antimalarial drugs is one of the most important problems to global malaria control. The study assess the evolution of the different resistance markers over time and the possible influence of the interventions and treatment changes that have been made in Equatorial Guinea.Methods: 1223 biological samples distributed from 1999 to 2019 were included in the study. The screening of the mutations in pfdhfr, pfdhps, pfmdr1 and pfcrt genes were carried out by nested PCR and RFLPs, and the study of pfk13 genes was carried out by nested PCR, followed by sequencing to determine the presence of mutations Results: the haplotypes partially and fully resistant (pfdhfr + pfdhps) increase over time. In 2019, the fully resistant is increasing although super resistant remains lower. There is also a continued decline over time in pfmdr1 and pfcrt gene mutations. Since 2008, when ACTs were introduced in the country, the number of mutations detected in pfk13 has been increasing over time, with more mutations being observed in 2019. In this year, were detected 2 synonymous and 5 non-synonymous mutations, although are not related to resistance to ACTs. In addition, the non-synonymous A578S mutation, the most frequent on the African continent, was detected in 2013, although it has not been detected in the following years.Conclusions: The withdrawal of the use of CQ as a treatment in the country has been effective over time, as wild-type parasite populations outnumber mutant populations. The upward trend observed in SP resistance markers evidence its misuse alone or in combination with AS or AQ in some areas of the country, this allows selective pressure from SP to continue. SNPs 540E and 581G do not exceed the limit of 50% and 10% respectively, which means that SP as an IPT is still effective in the country. As for the pfk13 gene, no mutations have been detected in relation to resistance to ACTs. However, in 2019 there is a greater accumulation of non-synonymous mutations compared to years prior to 2008.

show abstract

“…At present, severe malaria is treated with drugs such as chloroquine, sulfadoxine-pyrimethamine, quinine, and artemisinin and its derivatives (artemether, artesunate). However, two of the safest and cost-effective drugs, chloroquine and sulfadoxine-pyrimethamine, have lost their efficacy in most malaria-endemic countries because of drug resistance (Lin et al, 2020;Mharakurwa et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

Safety and Efficacy of Adjunctive Therapy With Artesunate in the Treatment of Severe Malaria: A Systematic Review and Meta-Analysis

et al. 2020

View full text Add to dashboard Cite

Objective: The purpose of this meta-analysis of longitudinal studies is to determine the safety and efficacy of artesunate combined with other forms of adjunctive therapies for severe malaria.Methods: Following the PRISMA guidelines, we searched multiple databases with the search terms “artesunate” and “adjunctive therapy” and “severe malaria” in July 2020. If the search showed a randomized controlled trial, the study was included in this meta-analysis. The random-effects model was used to calculate the combined incidence rate and relative risk or risk difference.Results: This meta-analysis included nine longitudinal studies with 724 participants. We found that the mortality rates in the artesunate monotherapy group and the artesunate + adjuvant therapy group are similar (RD = −0.02, 95% confidence interval: −0.06–0.02). The incidence of adverse reactions in the artesunate monotherapy group and the artesunate + adjuvant therapy group was also similar.Conclusion: No significant differences in safety and efficacy were observed between the artesunate monotherapy group and the artesunate + adjuvant therapy group. Higher quality and rigorously designed randomized controlled studies are needed to validate our findings.

show abstract

<p>Trends in Molecular Markers Associated with Resistance to Sulfadoxine-Pyrimethamine (SP) Among <em>Plasmodium falciparum</em> Isolates on Bioko Island, Equatorial Guinea: 2011–2017</p>

Cited by 3 publications

References 41 publications

Temporal evolution of the resistance genotypes of Plasmodium falciparum in isolates from Equatorial Guinea during 20 years (1999 to 2019)

Temporal evolution of the resistance genotypes of Plasmodium falciparum in isolates from Equatorial Guinea during 20 years (1999 to 2019)

Temporal Evolution of the Resistance Genotypes of Plasmodium Falciparum in Isolates From Equatorial Guinea During 20 Years (1999 to 2019).

Safety and Efficacy of Adjunctive Therapy With Artesunate in the Treatment of Severe Malaria: A Systematic Review and Meta-Analysis

Contact Info

Product

Resources

About