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Seroprevalence of SARS-CoV-2 antibodies in children: a prospective multicentre cohort study
  1. Thomas Waterfield1,2,
  2. Chris Watson1,
  3. Rebecca Moore3,
  4. Kathryn Ferris4,
  5. Claire Tonry1,
  6. Alison Watt5,
  7. Claire McGinn3,
  8. Steven Foster6,
  9. Jennifer Evans7,
  10. Mark David Lyttle8,9,
  11. Shazaad Ahmad10,11,
  12. Shamez Ladhani12,
  13. Michael Corr4,
  14. Lisa McFetridge13,
  15. Hannah Mitchell13,
  16. Kevin Brown14,
  17. Gayatri Amirthalingam15,
  18. Julie-Ann Maney16,
  19. Sharon Christie17
  1. 1Queen's University Belfast Wellcome-Wolfson Institute for Experimental Medicine, Belfast, UK
  2. 2Emergency Department, Children's Health Ireland at Temple Street, Dublin D01 YC67, Ireland
  3. 3General Paediatrics, Royal Belfast Hospital for Sick Children, Belfast, UK
  4. 4Belfast Health and Social Care Trust, Belfast, UK
  5. 5Regional Virus Laboratory, Belfast Health and Social Care Trust, Belfast, UK
  6. 6Emergency Department, Royal Hospital for Children, Glasgow, UK
  7. 7Cardiff and Vale University Health Board, Cardiff, UK
  8. 8Emergency Department, University Hospitals Bristol NHS Foundation Trust, Bristol, UK
  9. 9Health and Applied Sciences, University of the West of England, Bristol, UK
  10. 10Department of Virology, Manchester Medical Microbiology Partnership, Manchester University NHS Foundation Trust, Manchester, Greater Manchester, UK
  11. 11Manchester Academic Health Science Centre, Manchester, UK
  12. 12Immunisation and Countermeasures Division, Public Health England, London, UK
  13. 13Mathematical Sciences Research Centre, Queen's University Belfast, Belfast, UK
  14. 14Virus Reference Department, Public Health England, Colindale, UK
  15. 15Immunisation,Hepatitis & Blood Safety Department, Public Health England Immunisation and Countermeasures Division, London, UK
  16. 16Emergency Department, Royal Belfast Hospital for Sick Children, Belfast, UK
  17. 17Paediatric Infectious Diseases, Royal Belfast Hospital for Sick Children, Belfast, UK
  1. Correspondence to Dr Thomas Waterfield, Emergency Department, Children's Health Ireland at Temple Street, Dublin D01 YC67, Ireland; thomas.waterfield{at}


Background Studies based on molecular testing of oral/nasal swabs underestimate SARS-CoV-2 infection due to issues with test sensitivity, test timing and selection bias. The objective of this study was to report the presence of SARS-CoV-2 antibodies, consistent with previous infection.

Design This multicentre observational cohort study, conducted between 16 April to 3 July 2020 at 5 UK sites, recruited children of healthcare workers, aged 2–15 years. Participants provided blood samples for SARS-CoV-2 antibody testing and data were gathered regarding unwell contacts and symptoms.

Results 1007 participants were enrolled, and 992 were included in the final analysis. The median age of participants was 10·1 years. There were 68 (6.9%) participants with positive SARS-CoV-2 antibody tests indicative of previous SARS-CoV-2 infection. Of these, 34/68 (50%) reported no symptoms prior to testing. The presence of antibodies and the mean antibody titre was not influenced by age. Following multivariable analysis four independent variables were identified as significantly associated with SARS-CoV-2 seropositivity: known infected household contact OR=10.9 (95% CI 6.1 to 19.6); fatigue OR=16.8 (95% CI 5.5 to 51.9); gastrointestinal symptoms OR=6.6 (95% CI 3.0 to 13.8); and changes in sense of smell or taste OR=10.0 (95% CI 2.4 to 11.4).

Discussion Children demonstrated similar antibody titres in response to SARS-CoV-2 irrespective of age. Fatigue, gastrointestinal symptoms and changes in sense of smell or taste were the symptoms most strongly associated with SARS-CoV-2 antibody positivity.

Trial registration number NCT0434740.

  • virology
  • epidemiology

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  • Twitter @mdlyttle, @shamezladhani, @julieannmaney

  • Correction notice This paper has been amended since it was published online. The end of the abstract originally refered to SARS-CoV-1 instead of SARS-CoV-2.

  • Contributors TW, CW, SL and SC conceived the study idea. TW, CW, SL, SC, RM, KF, CM, SF, JE, MDL, SA, MC, LM, HM and J-AM contributed to the design of the study. TW coordinated the running of the study including data management and site training. MC wrote the study protocol. MDL designed the electronic CRFs. RM coordinated and led the PPI group. SC, KF, SF, JE, SA and SL were site leads. CT, CW, GA, KB and AW were responsible for performing laboratory testing. LM and HM provided statistical expertise and performed the statistical analysis. All authors contributed to the writing of the manuscript.

  • Funding This work was supported by HSC R&D Division, Public Health Agency Ref: COM/5596/20. This funding source had no role in the design of this study and will not have any role during its execution, analyses, interpretation of the data or decision to submit the result.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Ethics approval Ethical approval was obtained from the London - Chelsea Research Ethics Committee (REC Reference - 20/HRA/1731) and the Belfast Health & Social Care Trust Research Governance (Reference 19147TW-SW).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available in a public, open access repository. All of the individual participant data collected during this study will be available (including data dictionaries) on the Queen’s University Belfast database within 3 months of completion of the study.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.

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