{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T06:09:21Z","timestamp":1789711761072,"version":"4.0.1"},"reference-count":36,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T00:00:00Z","timestamp":1789689600000},"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. Epidemiol."],"abstract":"<jats:p>\n                    Rapid and accurate malaria diagnosis is essential for effective treatment and malaria control. In Kenya, most malaria testing relies on\n                    <jats:italic>P. falciparum<\/jats:italic>\n                    histidine-rich protein 2 (PfHRP2)-based rapid diagnostic tests (RDTs). However, deletions in the\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2\/\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 genes can lead to false-negative RDT results, which can sustain transmission and worsen clinical outcomes. This study assessed the prevalence and pattern of\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2,\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 and their respective flanking genes in archived samples collected before and after the nationwide rollout of PfHRP2-based RDTs in Kenya in 2012. A total of 350 archived whole-blood samples were analysed, comprising 95 pre-RDT samples (collected before the nationwide rollout of RDTs in Kenya) from 2003 to 2005 and 255 post-RDT samples (collected after the nationwide rollout of RDTs in Kenya) from 2013 to 2017 from multiple malaria-endemic regions of Kenya. Samples were first screened by quantitative Real-Time PCR to identify those with adequate parasite density for genotyping. Nested PCR assays were then used to genotype\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2,\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 and their flanking genes. Where available, PfHRP2-based RDT results were compared with molecular genotyping outcomes to investigate potential causes of false-negative RDT results. The overall prevalence of single\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2 or\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 deletions was low, at 0.3% (1\/317) and 1.3% (4\/317), respectively. All pre-RDT samples carried intact\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2 and\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 genes. Among post-RDT samples, deletions were rare 0.4% (1\/224) for\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2 gene only and 1.8% (4\/224) for\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 gene only\n                    <jats:italic>.<\/jats:italic>\n                    No sample exhibited a triple deletion of\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2 and both of its flanking genes or triple deletion of\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 and both of its flanking genes. The sensitivity of the PfHRP2-based RDT was 89.2% (174\/195). Notably, 95.2% of false-negative RDT results occurred in samples with intact\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2 and\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3, suggesting that low parasitemia or other factors, rather than gene deletions, were the primary cause of diagnostic failure. Overall,\n                    <jats:italic>pfhrp<\/jats:italic>\n                    2 and\n                    <jats:italic>pfhrp<\/jats:italic>\n                    3 deletions remained rare in the samples collected up to five years after the nationwide rollout of PfHRP2-RDTs in Kenya. However, continuous molecular surveillance is essential to identify emerging deletion hotspots and to ensure the sustained reliability of PfHRP2-based diagnostics as testing practices and parasites continue to evolve.\n                  <\/jats:p>","DOI":"10.3389\/fepid.2026.1817539","type":"journal-article","created":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T05:36:03Z","timestamp":1789709763000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Low prevalence of Plasmodium falciparum pfhrp2 and pfhrp3 gene deletions in archived samples collected before and after nationwide malaria-RDT rollout in Kenya"],"prefix":"10.3389","volume":"6","author":[{"given":"Martha N.","family":"Kivecu","sequence":"first","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]},{"name":"Centre for Biotechnology and Bioinformatics (CEBIB), University of Nairobi","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Victor","family":"Mobegi","sequence":"additional","affiliation":[{"name":"Centre for Biotechnology and Bioinformatics (CEBIB), University of Nairobi","place":["Nairobi, Kenya"]},{"name":"Department of Biochemistry, University of Nairobi","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cavin","family":"Mgawe","sequence":"additional","affiliation":[{"name":"Biosciences Department, KEMRI Wellcome Trust Research Programme","place":["Kilifi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brenda M.","family":"Kania","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]},{"name":"Centre for Biotechnology and Bioinformatics (CEBIB), University of Nairobi","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gladys C.","family":"Chemwor","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raphael O.","family":"Okoth","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edwin W.","family":"Mwakio","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George","family":"Obiero","sequence":"additional","affiliation":[{"name":"Centre for Biotechnology and Bioinformatics (CEBIB), University of Nairobi","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer M.","family":"Mutisya","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jackline A.","family":"Juma","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Agnes C.","family":"Cheruiyot","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin H.","family":"Opot","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amanda L.","family":"Roth","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernhards R.","family":"Ogutu","sequence":"additional","affiliation":[{"name":"Center for Clinical Research, Kenya Medical Research Institute (KEMRI)","place":["Nairobi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dennis W.","family":"Juma","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa (WRAIR\u2013A)","place":["Kisumu, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lynette Isabella","family":"Ochola-Oyier","sequence":"additional","affiliation":[{"name":"Biosciences Department, KEMRI Wellcome Trust Research Programme","place":["Kilifi, Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ben","family":"Andagalu","sequence":"additional","affiliation":[{"name":"Malaria Drug Resistance program, Kenya Medical Research Institute (KEMRI)\/Walter Reed Army Institute of Research \u2013 Africa 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