{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T00:26:59Z","timestamp":1768955219751,"version":"3.49.0"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T00:00:00Z","timestamp":1768867200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Direcci\u00f3n General de Investigaciones of Universidad Santiago de Cali","award":["DGI-01-2026"],"award-info":[{"award-number":["DGI-01-2026"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Background and Clinical Significance: Malaria remains a significant public health issue in Latin America, where Plasmodium vivax predominates but P. falciparum continues to circulate. Mixed-species infections are uncommon and can pose diagnostic challenges, particularly when parasite densities differ markedly, increasing the risk of underdetecting P. falciparum with conventional methods. Case report: We report a 9-year-old boy from an endemic area with a six-day febrile syndrome. Thick smear and peripheral blood film microscopy, complemented by rapid diagnostic tests for pan-Plasmodium and HRP2 antigens, confirmed a mixed infection with P. vivax (5500 parasites\/\u00b5L) and P. falciparum (562 parasites\/\u00b5L). The patient was hemodynamically stable, without severe malaria criteria, and laboratory values were within normal limits. Following confirmation of normal glucose-6-phosphate dehydrogenase activity, treatment with artemether\u2013lumefantrine was initiated, followed by primaquine for hypnozoite eradication. Clinical evolution was favorable, with progressive defervescence, treatment tolerance, and documented parasite clearance. Conclusions: This case illustrates the risk of underestimating P. falciparum in mixed infections with disparate parasitemias and highlights the value of integrated diagnostic approaches in resource-limited endemic settings. It also underscores surveillance limitations that can misclassify mixed infections, potentially affecting epidemiological estimates and treatment strategies. Timely recognition and comprehensive diagnostic evaluation are essential to ensure appropriate antimalarial therapy, prevent complications, and inform public health interventions in regions where both species coexist.<\/jats:p>","DOI":"10.3390\/children13010145","type":"journal-article","created":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T11:27:58Z","timestamp":1768908478000},"page":"145","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Pediatric Mixed Plasmodium vivax\u2013P. falciparum Infection with Disparate Parasitemias: Diagnostic and Surveillance Challenges"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5012-5555","authenticated-orcid":false,"given":"Jose Luis","family":"Estela-Zape","sequence":"first","affiliation":[{"name":"Faculty of Health, Universidad Santiago de Cali, Cali 760035, Colombia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,20]]},"reference":[{"key":"ref_1","unstructured":"WHO (2024). 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