Evidence map›Paper›PMID 40972560›Full record

ArticleThe Journal of infectious diseases2026

Spontaneous Clearance of Polymerase Chain Reaction-Positive Plasmodium vivax Parasitemia in Northwestern Thailand: An Epidemiological Perspective.

Pyae Linn Aung, Piyarat Sripoorote, Pattamaporn Petchvijit, Kritsana Suk-Aum, Khaing Zin Zin Htwe, Saranath Lawpoolsri, Wang Nguitragool, Liwang Cui, Jaranit Kaewkungwal, Jetsumon Sattabongkot

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Article in The Journal of infectious diseases, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Pyae Linn AungMahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.ORCID 0000-0003-4635-3701
Piyarat SripooroteMahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Pattamaporn PetchvijitMahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Kritsana Suk-AumCenter of Vector Borne Disease Control 2.3, Ministry of Public Health, Maesot, Thailand.
Khaing Zin Zin HtweMahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.ORCID 0009-0001-3253-8353
Saranath LawpoolsriDepartment of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Wang NguitragoolMahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Liwang CuiDivision of Infectious Diseases and International Medicine, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.ORCID 0000-0002-8338-1974
Jaranit KaewkungwalDepartment of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Jetsumon SattabongkotMahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.ORCID 0000-0002-3938-4588

Funding

Southeast Asia Malaria Research CenterU19AI089672 · NIAID · UNIVERSITY OF SOUTH FLORIDA · PI CUI, LIWANG · 2010 to 2023
$28.9M
The changing landscape of human and zoonotic malaria in Southeast AsiaU19AI181583 · NIAID · MAHIDOL UNIVERSITY · PI Daibin Zhong · 2024 to 2026
$3.6M
Training in Malaria Research in MyanmarD43TW011509 · FIC · UNIVERSITY OF SOUTH FLORIDA · PI LIWANG CUI · 2021 to 2026
$1.2M
FIC NIH HHS D43 TW011509Mahidol UniversityNational Institute of Allergy and Infectious DiseasesNational Science Research and Innovation FundNIAID NIH HHS U19 AI089672NIAID NIH HHS U19 AI181583NIH HHS TW011509NIH HHS U19AI089672NIH HHS U19AI181583
6 · The paper itself

Abstract

backgroundAsymptomatic, low-density Plasmodium vivax infections pose a significant challenge to malaria elimination because of their subclinical presentation and potential for ongoing transmission. However, the natural history of such untreated infections, including the extent to which they resolve spontaneously, remains poorly understood and has not been systematically studied for P. vivax.

methodsWe conducted a longitudinal cohort study from 2018 to 2023 in northwestern Thailand, incorporating 14 rounds of mass blood surveys (MBS) covering approximately 5000 individuals. Blood samples were screened for P. vivax using both microscopy and polymerase chain reaction (PCR). Participants with PCR-positive, submicroscopic parasitemia were followed in subsequent surveys to assess infection dynamics. Turnbull survival analysis estimated time to spontaneous clearance, and Cox proportional hazards models identified demographic factors associated with clearance.

resultsAmong 210 P. vivax infections detected by microscopy and/or PCR, 154 were detected only by PCR. After excluding individuals lost to follow-up or with coinfections, 101 participants were analyzed. Most infections (72, 69.9%) cleared spontaneously within 3 subsequent MBS. Turnbull survival analysis revealed that the probability of persistent infections declined to 25.0% (95% CI: 4.0-100.0) by day 47 and 7.0% (95% CI: 1.0-38.0) by day 232. Clearance was not significantly associated with age, sex, nationality, occupation, or education.

conclusionsA considerable proportion of submicroscopic P. vivax infections resolved spontaneously without treatment, providing the first field-based evidence of this phenomenon. These findings suggest a role for naturally acquired immunity and highlight implications for surveillance and targeted intervention strategies in malaria elimination contexts.

Indexed as

Malaria, VivaxParasitemiaPlasmodium vivaxAdolescentAdultAgedChildChild, PreschoolFemaleHumansLongitudinal StudiesMaleMiddle AgedPolymerase Chain ReactionRemission, SpontaneousThailandasymptomaticmalaria eliminationPCRPlasmodium vivaxspontaneous clearance

Identifiers

PMID40972560
PMCPMC13016805

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LicenceCC BY-NC-ND
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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 OpenQuestion graph.