Evidence map›Paper›PMID 42373175›Full record

Observational studyBMJ open2026

Longitudinal serological detection of exposure to SARS-CoV-2 in a cohort of pregnant women in Malawi: a secondary analysis from a randomised controlled trial.

Louise M Randall, Nicholas Kiernan-Walker, Ernest Moya, Glory Mzembe, Alistair R D McLean, Rebecca Harding, Ramin Mazhari, Gomezgani Mhango, Katherine L Fielding, Ivo Mueller and 6 more

Abstract readObservational Study
In one paragraph

Observational study in BMJ open, 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

16 authors.

Louise M RandallInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.ORCID http://orcid.org/0009-0002-0391-1080
Nicholas Kiernan-WalkerInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.
Ernest MoyaThe Training and Research Unit of Excellence, Blantyre, Malawi.
Glory MzembeThe Training and Research Unit of Excellence, Blantyre, Malawi.ORCID http://orcid.org/0000-0002-7277-9987
Alistair R D McLeanInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.ORCID http://orcid.org/0000-0003-3449-7142
Rebecca HardingInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.ORCID http://orcid.org/0000-0003-4267-716X
Ramin MazhariInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.ORCID http://orcid.org/0000-0001-5057-5994
Gomezgani MhangoThe Training and Research Unit of Excellence, Blantyre, Malawi.
Katherine L FieldingInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.
Ivo MuellerInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.
Martin N MwangiThe Training and Research Unit of Excellence, Blantyre, Malawi.ORCID http://orcid.org/0000-0002-8358-4448
Sabine BraatInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.ORCID http://orcid.org/0000-0003-1997-3999
Kamija PhiriThe Training and Research Unit of Excellence, Blantyre, Malawi.
Sant-Rayn PasrichaInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.
Emily M ErikssonInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia eriksson@wehi.edu.au ataide.r@wehi.edu.au.ORCID http://orcid.org/0000-0002-7851-973X
Ricardo AtaídeInfection and Global Health, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia eriksson@wehi.edu.au ataide.r@wehi.edu.au.ORCID http://orcid.org/0000-0002-1014-0432

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveTo investigate whether IgG to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens could reveal undetected SARS-CoV-2 exposure in a cohort of Malawian pregnant women participating in the REVAMP clinical trial.

designA secondary analysis of serological samples from a randomised controlled trial of iron supplementation in pregnancy, which began recruiting women in November 2018 and had its last visit occurring in September 2021.

settingResource-limited setting in Zomba and Blantyre, Southern Malawi.

participantsPregnant women with ultrasound-confirmed singleton pregnancies in the second trimester, with haemoglobin <100 g/L and randomised at enrolment to receive either intravenous ferric carboxymaltose or standard oral iron, where no coronavirus disease 2019 (COVID-19) clinical cases or SARS-CoV-2 positive tests were reported during the pandemic (April 2020-September 2021). PRIMARY AND SECONDARY OUTCOMES: Primary outcome was the levels of antibodies and seropositivity to SARS-CoV-2 antigens in the cohort of women across the duration of the trial. Secondary outcomes were the impact of IgG levels and seropositivity to SARS-CoV-2 on pregnancy outcomes.

resultsAt delivery, IgG levels to SARS-CoV-2 antigens increased sharply by 18.5%-29.7% every 30 days during COVID-19 waves 2 and 3. Overall seropositivity reached 39.3% during the pandemic; however, 14.7% pre-pandemic seropositivity demonstrates cross-reactive antibody responses. Pandemic pregnancies showed improved outcomes with longer gestations (mean difference: 0.6 weeks (95% CI 0.2 to 0.9)) and higher birth weights (mean difference: 169.3 g (65.9-272.6)). SARS-CoV-2 IgG levels were not associated with pregnancy outcomes.

conclusionSerological testing was able to detect exposure to SARS-CoV-2 in a population without clinical indications of the disease, suggesting that serosurveillance is more sensitive than relying on clinical data to monitor pathogen exposure in the community. Additionally, this highlights pregnancy cohorts as valuable sentinel populations for infectious disease surveillance in resource-limited settings. TRIAL REGISTRATION NUMBER: This trial was prospectively registered at ANZCTR: ACTRN12618001268235.

Indexed as

Antibodies, ViralCOVID-19Immunoglobulin GPregnancy Complications, InfectiousSARS-CoV-2AdultCOVID-19 Serological TestingFemaleHumansLongitudinal StudiesMalawiPregnancyRandomized Controlled Trials as TopicYoung AdultAntibodies, ViralImmunoglobulin GCOVID-19INFECTIOUS DISEASESPregnancyPublic health

Identifiers

PMID42373175
PMCPMC13331037

What Socratic 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 Socratic graph.