Evidence of Artemisinin-Resistant Malaria in Africa.
By Betty Balikagala, Naoyuki Fukuda, Mie Ikeda, Osbert T. Katuro, Shin-Ichiro Tachibana, M. Yamauchi, Walter Opio, Sakurako Emoto, D. A. Anywar, E. Kimura and 5 more. New England Journal of Medicine, 2021
603 citations recorded by the source corpus.
BACKGROUND In the six Southeast Asian countries that make up the Greater Mekong Subregion, Plasmodium falciparum has developed resistance to derivatives of artemisinin, the main component of first-line treatments for malaria. Clinical resistance to artemisinin monotherapy in other global regions, including Africa, would be problematic. METHODS In this longitudinal study conducted in Northern Uganda, we treated patients who had P. falciparum infection with intravenous artesunate (a water-soluble artemisinin derivative) and estimated the parasite clearance half-life. We evaluated ex vivo susceptibility of the parasite using a ring-stage survival assay and genotyped resistance-related genes. RESULTS From 2017 through 2019, a total of 14 of 240 patients who received intravenous artesunate had evidence of in vivo artemisinin resistance (parasite clearance half-life, >5 hours). Of these 14 patients, 13 were infected with P. falciparum parasites with mutations in the A675V or C469Y allele in the kelch13 gene. Such mutations were associated with prolonged parasite clearance half-lives (geometric mean, 3.95 hours for A675V and 3.30 hours for C469Y, vs. 1.78 hours for wild-type allele; P<0.001 and P = 0.05, respectively). The ring-stage survival assay showed a higher frequency of parasite survival among organisms with the A675V allele than among those with the wild-type allele. The prevalence of parasites with kelch13 mutations increased significantly, from 3.9% in 2015 to 19.8% in 2019, due primarily to the increased frequency of the A675V and C469Y alleles (P<0.001 and P = 0.004, respectively). Single-nucleotide polymorphisms flanking the A675V mutation in Uganda were substantially different from those in Southeast Asia. CONCLUSIONS The independent emergence and local spread of clinically artemisinin-resistant P. falciparum has been identified in Africa. The two kelch13 mutations may be markers for detection of these resistant parasites. (Funded by the Japan Society for the Promotion of Science and others.).
Subfields: Public Health, Environmental and Occupational Health, Radiology, Nuclear Medicine and Imaging
View Paper: https://www.semanticscholar.org/paper/94ce022e9daf6da0a3118c0f40a49e8775df159f
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
- Frankie M. T. Lyons
- Mikha Gabriela
- M. Dietrich
- W. Tham
Citations in the corpus
- Plasmodium 6-Cysteine Proteins: Functional Diversity, Transmission-Blocking Antibodies and Structural Scaffolds (2022, background): “The epitope is conserved as all major polymorphisms identified from 2512 analyzed sequences from Africa and Asia are outside the binding site of LMIV230-01.”