{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T01:43:31Z","timestamp":1788227011411,"version":"build-2803163510"},"reference-count":27,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,6,30]],"date-time":"2025-06-30T00:00:00Z","timestamp":1751241600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013885","name":"National Institutes of Health (NIH), Ministry of Health (MOH)","doi-asserted-by":"publisher","award":["NMRR-21-1162-60367"],"award-info":[{"award-number":["NMRR-21-1162-60367"]}],"id":[{"id":"10.13039\/501100013885","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>The risk of non-human primate (NHP) malaria transmission to humans is increasing, with Plasmodium knowlesi and Plasmodium cynomolgi emerging as significant zoonotic threats, particularly in Malaysia. While P. knowlesi is well-documented, P. cynomolgi infections in humans remain underreported, largely due to diagnostic challenges. Routine microscopy and standard molecular diagnostic tools often misdiagnose P. cynomolgi infections as P. vivax due to morphological similarities and genetic homology. We report a new case of a human P. cynomolgi infection misdiagnosed as Plasmodium vivax in a 32-year-old male with no prior malaria history or travel to endemic countries. The initial diagnoses made by the microscopy and qPCR conducted by the Kota Bharu Public Health Laboratory in Kelantan identified the infection as P. vivax. However, cross-examination by the Institute for Medical Research (IMR) revealed the presence of mixed-species infection, prompting further analysis. The real-time PCR and sequencing performed at MAPELAB, Spain, confirmed the co-infection of P. vivax and P. cynomolgi. This case highlights the diagnostic limitations in detecting P. cynomolgi, which shares high genetic similarity with P. vivax, leading to potential cross-reactivity and diagnostic inaccuracies. As P. cynomolgi emerges as the second zoonotic malaria species after P. knowlesi capable of infecting humans in Southeast Asia, improved diagnostic methods are urgently needed. Enhanced molecular diagnostics and comprehensive epidemiological studies are essential to elucidate transmission dynamics, assess public health implications, and inform effective malaria control strategies.<\/jats:p>","DOI":"10.3390\/pathogens14070651","type":"journal-article","created":{"date-parts":[[2025,7,1]],"date-time":"2025-07-01T06:56:54Z","timestamp":1751353014000},"page":"651","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Molecular and Microscopic Challenges in Detecting Plasmodium cynomolgi Co-Infections with Plasmodium vivax: A Case Report"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-2956-1476","authenticated-orcid":false,"given":"Mohd Adilin","family":"Yaacob","sequence":"first","affiliation":[{"name":"Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Setia Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raden Shamilah","family":"Radin Hisam","sequence":"additional","affiliation":[{"name":"Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Setia Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nor","family":"Parina Ismail","sequence":"additional","affiliation":[{"name":"Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Setia Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2638-3789","authenticated-orcid":false,"given":"Noor Azian","family":"Md Yusuf","sequence":"additional","affiliation":[{"name":"Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Setia Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1903-6711","authenticated-orcid":false,"given":"Jose Miguel","family":"Rubio Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Malaria & Emerging Parasitic Diseases Laboratory, Parasitology Department, National Microbiology Centre, Instituto de Salud Carlos III, Cra. Majadahonda Pozuelo Km. 2, 28220 Majadahonda, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suhana","family":"Hashim","sequence":"additional","affiliation":[{"name":"Kota Bharu Public Health Laboratory (KBPHL), Kota Bharu 16010, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tam Jenn","family":"Zhueng","sequence":"additional","affiliation":[{"name":"Disease Control Division, Ministry of Health, Putrajaya 62590, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"73","DOI":"10.4103\/tp.tp_79_22","article-title":"Primate Malaria of Human Importance","volume":"13","author":"Mewara","year":"2023","journal-title":"Trop. 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