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Using BCG vaccination to protect against COVID-19: when reality fails to meet expectation

Nature Reviews Immunology volume 24, pages 83–84 (2024)Cite this article

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While anticipating the development of a COVID-19-specific vaccine, several randomized controlled trials (RCTs) explored the potential of BCG vaccination to protect against COVID-19, based on trials demonstrating beneficial effects of BCG vaccination on unrelated infections and all-cause mortality in neonates in high-mortality geographical settings. Results are now available from 12 RCTs, which suggest that BCG vaccination is not an effective intervention against COVID-19. That the BCG–COVID-19 trials failed to meet expectation emphasizes the importance of rigorous clinical trials to validate hypotheses, even in urgent situations such as a pandemic.

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Authors and Affiliations

  1. Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia

    Laure F. Pittet, Christie C. A. Noble, Nicole L. Messina & Nigel Curtis

  2. Murdoch Children’s Research Institute, Parkville, Victoria, Australia

    Laure F. Pittet, Christie C. A. Noble, Nicole L. Messina & Nigel Curtis

  3. Immunology-Vaccinology and Paediatric Infectious Diseases Unit, Faculty of Medicine, Geneva University Hospitals, Geneva, Switzerland

    Laure F. Pittet

  4. Infectious Diseases, The Royal Children’s Hospital Melbourne, Parkville, Victoria, Australia

    Christie C. A. Noble & Nigel Curtis

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  1. Laure F. Pittet
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  2. Christie C. A. Noble
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  4. Nigel Curtis
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Correspondence to Laure F. Pittet or Nigel Curtis.

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Pittet, L.F., Noble, C.C.A., Messina, N.L. et al. Using BCG vaccination to protect against COVID-19: when reality fails to meet expectation. Nat Rev Immunol 24, 83–84 (2024). https://doi.org/10.1038/s41577-024-00992-z

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