Evidence map›Paper›PMID 42139233›Full record

ArticlePloS one2026

Evaluation of plasma anti-CS3 and anti-LTB IgG avidity among Zambian children vaccinated with ETVAX.

Cynthia Mubanga, Mutale Mubanga, Obvious Nchimunya Chilyabanyama, Masauso Phiri, Caroline C Chisenga, Richard H Glashoff, Roma Chilengi

Abstract read
In one paragraph

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

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

0 citing papers in PubMed.

No citing paper in PubMed yet.

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.

Cynthia MubangaBasic science and immunology Department, Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.ORCID https://orcid.org/0000-0001-7557-6352
Mutale MubangaLaboratory Servies Department, Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.
Obvious Nchimunya ChilyabanyamaResearch Department, Maryland Global Initiatives Corporation (MGIC), Kabulonga, Lusaka, Zambia.ORCID https://orcid.org/0000-0003-3593-1895
Masauso PhiriDepartment of Pathology and Microbiology, University of Zambia, School of Medicine, Lusaka, Zambia.
Caroline C ChisengaBasic science and immunology Department, Centre for Infectious Disease Research in Zambia, Lusaka, Zambia.ORCID https://orcid.org/0000-0002-7850-7915
Richard H GlashoffDivision of Medical Microbiology & Immunology, Department of Pathology, Stellenbosch University & National Health Laboratory Service, Tygerberg Hospital Francie van Zijl Drive, Tygerberg, Cape Town, South Africa.
Roma ChilengiZambia National Public Health Institute, Corner of Chaholi & Addis Ababa Roads,Rhoadespark, Lusaka, Zambia.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundEnterotoxigenic Escherichia coli (ETEC) remains a major cause of diarrheal disease in low- and middle-income countries (LMICs). To curb ETEC related diarrhoea, several candidate vaccines are in development, with ETVAX® being the most advanced. Although immunogenicity studies have primarily focused on measuring antibody titres, assessing antibody avidity offers additional valuable insight into antibody quality and immune maturity. This study assessed anti-CS3 and anti-LTB IgG avidity in Zambian children to better understand vaccine-induced antibody responses in an endemic setting.

methodsChildren aged 6-23 months (n = 60) received three quarter-doses of ETVAX® with dmLT adjuvant on days 1, 14, and 90. Plasma samples collected at baseline prior to the first vaccination (Day 1; V1), seven days after the second dose (Day 22; V5), and seven days after the third dose (Day 97; V7) were analysed by limiting antigen dilution ELISA to calculate avidity indices (AI). Naïve classification was performed using titre-based thresholds (20th percentile of baseline titres) and avidity-defined naivety (AI < 0.5). Receiver operating characteristic (ROC) analysis was used to evaluate the discriminatory performance of avidity indices against titre-defined naïve status.

resultsBaseline avidity was detectable for both CS3 and LTB, consistent with prior natural exposure. Mean CS3 IgG avidity decreased from 0.7 at baseline to 0.6 after the third dose (p < 0.001), while LTB IgG avidity showed transient decreases but no net gain. Naïve classification at baseline revealed that 9/60 children had titres but low avidity (functional naivety), and 6/60 had waned titres but high avidity. Only one child was naïve by both criteria for CS3, and none for LTB. ROC analysis demonstrated moderate discrimination for CS3 (AUC = 0.65; optimal cut-off AI = 0.36) but poor discrimination for LTB (AUC = 0.30).

conclusionIn this endemic population, ETVAX® induced strong antibody titres but minimal changes in avidity over time, with notable inter-individual variability. ROC analysis highlighted context-specific limitations in using avidity to discriminate immune maturity. Together, these findings suggest that while antibody avidity may provide complementary information on antibody quality, its interpretation should be cautious and considered alongside antibody titres in endemic settings.

Indexed as

Antibodies, BacterialAntibody AffinityEnterotoxigenic Escherichia coliEscherichia coli InfectionsEscherichia coli VaccinesImmunoglobulin GFemaleHumansInfantMaleVaccinationZambiaAntibodies, BacterialEscherichia coli VaccinesImmunoglobulin G

Identifiers

PMID42139233
PMCPMC13178912

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

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 OpenQuestion graph.