Evidence map›Paper›PMID 40503635›Full record

ArticleThe Journal of infectious diseases2026

Digital PCR Reveals High PvDBP1 but not PvEBP/DBP2 and PvRBP2b Copy Number in Plasmodium vivax From Duffy-Negative Individuals in Central Africa.

Bernis Neneyoh Yengo, Victoria Ruszin, Cheikh Cambel Dieng, Canelle Kipayko, Nontokozo Mdluli, Bate Ayukenchengamba, Ebai Calvin Bisong, Doris Tabi Sona, Zidedine Nematchoua Weyou, Irene Sumbele and 2 more

Abstract read
In one paragraph

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. Cited by 1 paper.

0numbers the graph read from it
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

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

1 citing paper in PubMed.

  1. 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

12 authors.

Bernis Neneyoh YengoDepartment of Microbiology and Immunology, College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA.ORCID 0000-0001-6200-5841
Victoria RuszinDepartment of Microbiology and Immunology, College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA.
Cheikh Cambel DiengDepartment of Microbiology and Immunology, College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA.
Canelle KipaykoDepartment of Microbiology and Immunology, College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA.
Nontokozo MdluliDepartment of Microbiology and Immunology, College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA.
Bate AyukenchengambaDepartment of Animal Biology and Conservation, Faculty of Science, University of Buea, Buea, Cameroon.
Ebai Calvin BisongDepartment of Medical Laboratory Science, University of Bamenda, Bamenda, Cameroon.
Doris Tabi SonaDepartment of Animal Biology and Conservation, Faculty of Science, University of Buea, Buea, Cameroon.
Zidedine Nematchoua WeyouDepartment of Animal Biology and Conservation, Faculty of Science, University of Buea, Buea, Cameroon.
Irene SumbeleDepartment of Animal Biology and Conservation, Faculty of Science, University of Buea, Buea, Cameroon.
Helen Kuokuo KimbiDepartment of Biomedical Sciences, University of Bamenda, Bamenda, Bamenda, Cameroon.
Eugenia LoDepartment of Microbiology and Immunology, College of Medicine, Drexel University, Philadelphia, Pennsylvania, USA.

Funding

Plasmodium vivax Erythrocyte Invasion Mechanisms and Humoral Immune Response in Duffy Negative AfricansR01AI162947 · NIAID · UNIVERSITY OF NORTH CAROLINA CHARLOTTE · PI Eugenia Lo · 2022 to 2026
$3.4M
A longitudinal cohort study of Plasmodium vivax relapses in Central AfricaR21AI190606 · NIAID · DREXEL UNIVERSITY · PI Eugenia Lo · 2025 to 2026
$397k
Drexel UniversityNIAID NIH HHS R01 AI162947NIAID NIH HHS R21 AI190606
6 · The paper itself

Abstract

backgroundVivax malaria, once thought rare in Duffy-negative Africans, is now reported in various parts of Africa, suggesting alternate invasion mechanisms and parasite adaptability to Duffy-null (DN) cells. One hypothesis is that copy number variation (CNV) of genes involved in erythrocyte invasion may impact parasite invasion capability and/or host immune evasion, particularly in Duffy-negative individuals.

methodUsing novel digital polymerase chain reaction (PCR), we assessed CNV of 3 key erythrocyte-binding genes of Plasmodium vivax isolated from DN individuals in 3 ecoepidemiological zones of Cameroon. For a subset of samples, we compare digital PCR (dPCR) results with quantitative PCR (qPCR) and PCR diagnostic approaches.

resultsPvDBP1 duplications were detected in approximately 92% of DN P. vivax samples, compared to approximately 10% of the samples with multicopy PvEBP/DBP2 and PvRBP2b. A significant positive correlation was detected between PvDBP1 CNV and parasite load among the samples. Both Malagasy- and Cambodian-type PvDBP1 duplications were detected. About one-third of the samples harbored both duplication types and these samples were exclusively in northern highlands of Cameroon, suggesting either polyclonal infections or a third duplication type.

conclusionsMulticopy PvDBP1 across all study sites may imply significant parasite adaptability and improved parasite invasion, potentially influencing parasitemia. This was confirmed by the significantly higher parasitemia observed in samples with Cambodian type and those with both duplication types compared to ones with no duplication. Furthermore, our data showed CNV analysis by qPCR may not be as precise as dPCR, particularly for low-parasitemia DN P. vivax samples. Predominantly low PvEBP/DBP2 and PvRBP2b CNV raises questions to their role in parasite adaptation to invading DN erythrocytes.

Indexed as

Antigens, ProtozoanDNA Copy Number VariationsMalaria, VivaxPlasmodium vivaxPolymerase Chain ReactionProtozoan ProteinsAdultCameroonDuffy Blood-Group SystemFemaleHumansMaleReceptors, Cell SurfaceYoung AdultAntigens, ProtozoanDuffy Blood-Group SystemProtozoan ProteinsReceptors, Cell SurfaceCentral Africacopy number variationsDuffy negativeerythrocyte binding genesparasite loadPlasmodium vivax

Identifiers

PMID40503635
PMCPMC13322635

What Socratic holds

Textmetadata
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Registered trials

None linked

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.