Evidence map›Paper›PMID 41264599›Full record

ArticlePloS one2025

Persistent low-density infection in areas at risk of malaria reintroduction in Malaysia.

Adela Ida Jiram, Shamilah Hisam, Mohd Hafizi Abdul Hamid, Jenarun Jelip, Rahmah Noordin, Kamarul Imran Musa, Nurhainis Ogu Salim, Noor Azian Md Yusuf, Nur Fariha Amir, Aliaa Rasyidina and 6 more

Abstract read
In one paragraph

Article in PloS one, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing 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

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

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

2 citing papers in PubMed.

  1. Article
  2. Article
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

16 authors.

Adela Ida JiramParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.ORCID https://orcid.org/0000-0001-9669-6927
Shamilah HisamParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.
Mohd Hafizi Abdul HamidDisease Control Division, Ministry of Health Malaysia, Putrajaya, Malaysia.
Jenarun JelipDepartment of Public Health Medicine, Faculty of Medicine and Health Sciences, University Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia.
Rahmah NoordinDepartment of Parasitology and Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Cheras, Kuala Lumpur, Malaysia.ORCID https://orcid.org/0000-0001-7583-0752
Kamarul Imran MusaDepartment of Community Medicine, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia.
Nurhainis Ogu SalimParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.ORCID https://orcid.org/0000-0001-6568-5651
Noor Azian Md YusufParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.
Nur Fariha AmirParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.ORCID https://orcid.org/0000-0002-4797-0683
Aliaa RasyidinaParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.
Nor Parina IsmailParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.
Dg Izyan Hazwani AzizParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.
Nur Hafizah AbdullahParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.
Aqidah KepParasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Shah Alam, Selangor, Malaysia.
Zaini HussinKelantan State Health Department, Wisma Persekutuan, Kota Bharu, Kelantan, Malaysia.
Aziah IsmailInstitute for Research in Molecular Medicine (INFORMM), Health Campus, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Malaysia successfully achieved zero indigenous human malaria cases since 2018. However, challenges persist from Plasmodium knowlesi (zoonotic malaria) and low-density infections, posing reintroduction risks in previously malaria-free areas. Addressing these hidden infections is critical for sustaining Malaysia's elimination gains. This study investigated the persistence of low-density malaria transmission in high-risk localities declared malaria-free for at least three consecutive years. A community-based cross-sectional survey was conducted from June to October 2020 in 23 high-receptivity localities across Sabah, Perak, Kelantan, and Johor. Blood samples from asymptomatic residents were screened via conventional microscopy and nested PCR (nPCR) targeting the Plasmodium 18S rRNA gene, with positive nPCR products species-determined. Sociodemographic and geospatial data were analyzed for associations with infection status. Of 3,322 asymptomatic individuals, no infections were detected by microscopy, whereas nPCR revealed a low-density malaria prevalence of 1.86% (62/3,322). Infections comprised P. malariae (40.3%), P. vivax (29.0%), P. knowlesi (24.2%), P. falciparum (1.6%), P. cynomolgi (1.6%), and mixed P. vivax/P. knowlesi (3.2%). All PCR-positive cases originated from Sabah and an Orang Asli settlement in Perak. Adults (≥17 years) constituted the majority (~68%), with no significant difference in prevalence by gender or previous malaria history (p > 0.05). Asymptomatic low-density malaria infections persist in purportedly malaria-free communities, remaining undetectable by routine microscopy. These hidden parasite reservoirs pose a risk for malaria reintroduction, especially in receptive areas. Malaria surveillance programs must thus incorporate highly sensitive diagnostic tools to detect low-density infections and safeguard elimination gains. Intensified, targeted interventions in identified "malaria hotspots", including community engagement and vector control, are crucial to eliminate residual foci and prevent disease resurgence.

Indexed as

MalariaPlasmodiumAdolescentAdultAgedChildChild, PreschoolCross-Sectional StudiesFemaleHumansInfantMalaysiaMaleMiddle AgedPlasmodium knowlesiPrevalenceRNA, Ribosomal, 18S

Identifiers

PMID41264599
PMCPMC12633942

What OpenQuestion holds

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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 OpenQuestion graph.