{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,2]],"date-time":"2026-11-02T23:34:44Z","timestamp":1793662484189,"version":"4.5.1"},"reference-count":34,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T00:00:00Z","timestamp":1780444800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Genet."],"abstract":"<jats:p>\n                    Artemisinin-based combination therapies (ACTs) remain the cornerstone of malaria treatment, yet the emergence of artemisinin partial resistance (ART-R) in Africa threatens their efficacy. ART-R is primarily associated with mutations in\n                    <jats:italic>Plasmodium falciparum<\/jats:italic>\n                    kelch13 (K13), notably R561H, which has been linked to delayed parasite clearance in East Africa. We genotyped 2,866\u00a0\n                    <jats:italic>P. falciparum<\/jats:italic>\n                    isolates from seven districts in Tanzania\u2019s Kagera region (2021\u20132023) using 121 molecular inversion probes (MIP) targeting key resistance loci to characterize trends in ART-R and other resistance markers. The WHO-validated K13 mutation R561H persisted in border districts of Karagwe and Kyerwa, with prevalence ranging from 14% to 26%, and appeared for the first time in Muleba in 2022 (10.0%) and Bukoba rural district (0.7%) in 2023, indicating eastward spread toward Lake Victoria. Regional prevalence of R561H rose from 5.5% in 2021 to 6.9% in 2023. Additional validated (A675V) and candidate (V568G, P441L) mutations were detected at low frequencies. Markers associated with reduced sensitivity to partner drugs showed minimal change. Early DHFR and DHPS mutations were near fixation and high-level resistance markers (DHFR I164L and DHPS A581G) exhibited marked gradients. These latest mutations are significantly spatially colocalized (weighted spearman R\n                    <jats:sup>2<\/jats:sup>\n                    = 0.58, P = 0.045) and co-occur within a number of individual genomes. These results highlight notable variation in mutation prevalence and underscore the importance of high-resolution surveillance to identify emerging hotspots and guide targeted interventions. Sustained molecular monitoring is critical to inform treatment policy, preserve ACT efficacy, and mitigate the risk of widespread resistance across East Africa.\n                  <\/jats:p>","DOI":"10.3389\/fgene.2026.1776108","type":"journal-article","created":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T22:10:16Z","timestamp":1780438216000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Temporal trends in artemisinin partial resistance and other antimalarial drug mutations in Plasmodium falciparum from Kagera region, Northwestern Tanzania, 2021\u20132023"],"prefix":"10.3389","volume":"17","author":[{"given":"Alfred","family":"Simkin","sequence":"first","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Brown University","place":["Providence, RI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salehe S.","family":"Mandai","sequence":"additional","affiliation":[{"name":"Ifakara Health Institute","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abebe A.","family":"Fola","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Brown University","place":["Providence, RI, United States"]},{"name":"Center for Computational Molecular Biology, Brown University","place":["Providence, RI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Neeva Wernsman","family":"Young","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Brown University","place":["Providence, RI, United States"]},{"name":"Center for Computational Molecular Biology, Brown University","place":["Providence, RI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacob","family":"Marglous","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Brown University","place":["Providence, RI, United States"]},{"name":"Center for Computational Molecular Biology, Brown University","place":["Providence, RI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dativa","family":"Pereus","sequence":"additional","affiliation":[{"name":"Ifakara Health Institute","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine","family":"Bakari","sequence":"additional","affiliation":[{"name":"Ifakara Health Institute","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rashid A.","family":"Madebe","sequence":"additional","affiliation":[{"name":"National Institute for Medical Research","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Misago D.","family":"Seth","sequence":"additional","affiliation":[{"name":"National Institute for Medical Research","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rule B.","family":"Mrengela","sequence":"additional","affiliation":[{"name":"Ifakara Health Institute","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angelina J.","family":"Kisambale","sequence":"additional","affiliation":[{"name":"Ifakara Health Institute","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gervas A.","family":"Chacha","sequence":"additional","affiliation":[{"name":"National Institute for Medical Research","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Celine 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Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sijenunu","family":"Aaron","sequence":"additional","affiliation":[{"name":"National Malaria Control Programme","place":["Dodoma, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdallah","family":"Lusasi","sequence":"additional","affiliation":[{"name":"National Malaria Control Programme","place":["Dodoma, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabrizio","family":"Molteni","sequence":"additional","affiliation":[{"name":"Swiss Tropical Public Health Institute","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ritha J. A.","family":"Njau","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Medical Entomology, Muhimbili University of Health and Allied Sciences","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stella","family":"Kajange","sequence":"additional","affiliation":[{"name":"President\u2019s Office, Regional Administration and Local Government","place":["Dodoma, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samwel L.","family":"Nhiga","sequence":"additional","affiliation":[{"name":"National Malaria Control Programme","place":["Dodoma, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ally","family":"Mohamed","sequence":"additional","affiliation":[{"name":"President\u2019s Office, Regional Administration and Local Government","place":["Dodoma, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan J.","family":"Juliano","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill","place":["Chapel Hill, NC, United States"]},{"name":"Curriculum of Genetics and Molecular Biology, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill","place":["Chapel Hill, NC, United States"]},{"name":"Institute for Global Health and Infectious Diseases, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill","place":["Chapel Hill, NC, United States"]},{"name":"Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill","place":["Chapel Hill, NC, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deus S.","family":"Ishengoma","sequence":"additional","affiliation":[{"name":"Ifakara Health Institute","place":["Dar es Salaam, Tanzania"]},{"name":"National Institute for Medical Research","place":["Dar es Salaam, Tanzania"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeffrey A.","family":"Bailey","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Brown University","place":["Providence, RI, United States"]},{"name":"Center for Computational Molecular Biology, Brown University","place":["Providence, RI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,3]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"e540","DOI":"10.1016\/S1473-3099(24)00427-4","article-title":"Alarming Plasmodium falciparum resistance to artemisinin-based combination therapy in Africa: the critical role of the partner drug","volume":"24","author":"Bj\u00f6rkman","year":"2024","journal-title":"Lancet Infect. 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