Molecular surveillance for polymorphisms associated with artemisinin-based combination therapy resistance in Plasmodium falciparum isolates collected in Mozambique, 2018

Abstract Background Due to the threat of emerging anti-malarial resistance, the World Health Organization recommends incorporating surveillance for molecular markers of anti-malarial resistance into routine therapeutic efficacy studies (TESs). In 2018, a TES of artemether-lumefantrine (AL) and artes...

Full description

Bibliographic Details
Published in:Malaria Journal
Main Authors: Arlindo Chidimatembue, Samaly S. Svigel, Alfredo Mayor, Pedro Aíde, Abel Nhama, Lídia Nhamussua, Arsénio Nhacolo, Quique Bassat, Crizólgo Salvador, Sónia Enosse, Abuchahama Saifodine, Eva De Carvalho, Baltazar Candrinho, Rose Zulliger, Ira Goldman, Venkatachalam Udhayakumar, Naomi W. Lucchi, Eric S. Halsey, Eusébio Macete
Format: Article in Journal/Newspaper
Language:English
Published: BMC 2021
Subjects:
Online Access:https://doi.org/10.1186/s12936-021-03930-9
https://doaj.org/article/7693976e046d498eb51bb172cfe049ba
Description
Summary:Abstract Background Due to the threat of emerging anti-malarial resistance, the World Health Organization recommends incorporating surveillance for molecular markers of anti-malarial resistance into routine therapeutic efficacy studies (TESs). In 2018, a TES of artemether-lumefantrine (AL) and artesunate-amodiaquine (ASAQ) was conducted in Mozambique, and the prevalence of polymorphisms in the pfk13, pfcrt, and pfmdr1 genes associated with drug resistance was investigated. Methods Children aged 6–59 months were enrolled in four study sites. Blood was collected and dried on filter paper from participants who developed fever within 28 days of initial malaria treatment. All samples were first screened for Plasmodium falciparum using a multiplex real-time PCR assay, and polymorphisms in the pfk13, pfcrt, and pfmdr1 genes were investigated by Sanger sequencing. Results No pfk13 mutations, associated with artemisinin partial resistance, were observed. The only pfcrt haplotype observed was the wild type CVMNK (codons 72–76), associated with chloroquine sensitivity. Polymorphisms in pfmdr1 were only observed at codon 184, with the mutant 184F in 43/109 (39.4%) of the samples, wild type Y184 in 42/109 (38.5%), and mixed 184F/Y in 24/109 (22.0%). All samples possessed N86 and D1246 at these two codons. Conclusion In 2018, no markers of artemisinin resistance were documented. Molecular surveillance should continue to monitor the prevalence of these markers to inform decisions on malaria treatment in Mozambique.