Evidence map›Paper›PMID 41413552›Full record

ArticleMalaria journal2025

Asymptomatic parasitaemia in a malaria pre-elimination setting in the Putumayo area of the Ecuadorian Amazon basin.

Jacob van der Ende, M Vanessa Dávila, Sandra Menting, Fabián E Sáenz, Thomas Hanscheid, Henk D F H Schallig, Martin P Grobusch

Abstract read
In one paragraph

Article in Malaria journal, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Jacob van der EndeHospital San Miguel, Fundación Quina Care Ecuador, Puerto El Carmen de Putumayo, Ecuador. j.vanderende@amsterdamumc.nl.
M Vanessa DávilaHospital San Miguel, Fundación Quina Care Ecuador, Puerto El Carmen de Putumayo, Ecuador.
Sandra MentingLaboratory for Experimental Parasitology, Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centre, Amsterdam, The Netherlands.
Fabián E SáenzCentro de Investigación para la Salud en América Latina, Centro de Investigación para la Salud en América Latina, Pontificia Universidad Católica del Ecuador, Quito, Ecuador.
Thomas HanscheidCenter for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Center, Location University of Amsterdam, Amsterdam, Netherlands.
Henk D F H SchalligLaboratory for Experimental Parasitology, Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Centre, Amsterdam, The Netherlands.
Martin P GrobuschCenter for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam University Medical Center, Location University of Amsterdam, Amsterdam, Netherlands.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundEcuador is approaching malaria elimination, but its Amazonian Putumayo canton borders regions in Colombia and Peru with high transmission intensity. This 'frontier' setting represents a critical vulnerability where asymptomatic infections may sustain transmission, undetected by routine surveillance.

methodsIn a repeated cross-sectional study during the 2023 rainy season, we surveyed 293 asymptomatic individuals in four riverine communities in Putumayo. We used a tiered diagnostic approach: rapid diagnostic tests (RDTs), expert microscopy, and real-time qPCR targeting the 18S rRNA gene.

resultsNo infections were detected by RDT (0/293). Microscopy identified three P. vivax infections (1.0%, 95% CI 0.2-2.4%). qPCR detected five positive cases (1.7%, 95% CI 0.6-3.9%), revealing two additional submicroscopic infections. The failure of a subsequent species-specific PCR and high Cq values (mean 32.6) indicated very low parasite densities. Infections were found only in the mid-to-late rainy season, predominantly in males.

conclusionsMolecular surveillance revealed a low-density, asymptomatic malaria reservoir missed entirely by RDTs, and partially by microscopy. This hidden burden represents a critical blind spot for Ecuador's elimination program. To achieve and sustain elimination, surveillance in such border regions must incorporate highly sensitive molecular tools and be supported by robust cross-border collaboration.

Indexed as

Asymptomatic InfectionsMalaria, VivaxParasitemiaPlasmodium vivaxAdolescentAdultAgedChildChild, PreschoolCross-Sectional StudiesEcuadorFemaleHumansInfantMaleMiddle AgedRNA, Ribosomal, 18SAmazon basinEcuadorMalariaP. falciparumPre-eliminationPutumayoP. vivax

Identifiers

PMID41413552
PMCPMC12828920

What Socratic holds

Textmetadata
LicenceCC BY-NC-ND
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.