An Old TB Vaccine Finds New Life in Coronavirus Trials

Studies are underway to test whether giving a shot of BCG vaccine could protect doctors and nurses against COVID-19.

Written byAnthony King
| 8 min read
bcg tuberculosis tb sars-cov-2 covid-19 coronavirus pandemic vaccine nonspecific effects trained immunity innate immune system response

Register for free to listen to this article
Listen with Speechify
0:00
8:00
Share

ABOVE: MODIFIED FROM © ISTOCK.COM, VISUAL GENERATION, FAIRYWONG, WENMEI ZHOU; © TASHA DIBIAGIO

One of the oldest vaccines could protect us against our newest infectious disease, COVID-19. The vaccine has been given to babies to protect them against tuberculosis for almost a century, but has been shown to shield them from other infections too, prompting scientists to investigate whether it can protect against the coronavirus.

This Bacille Calmette-Guérin (BCG) vaccine, named after two French microbiologists, consists of a live weakened strain of Mycobacterium bovis, a cousin of M. tuberculosis, the bacterium that causes tuberculosis. BCG has been given to more than 4 billion individuals, making it the most widely administered vaccine globally.

Because BCG protects babies against some viral infections in addition to TB, researchers decided to compare data from countries with and without mandatory BCG vaccination to see if immunization policies are linked to the number or severity of ...

Interested in reading more?

Become a Member of

The Scientist Logo
Receive full access to more than 35 years of archives, as well as TS Digest, digital editions of The Scientist, feature stories, and much more!
Already a member? Login Here

Related Topics

Meet the Author

  • anthony king

    Anthony King is a freelance science journalist based in Dublin, Ireland, who contributes to The Scientist. He reports on a variety of topics in chemical and biological sciences, as well as science policy and health. His articles have appeared in Nature, Science, Cell, Chemistry World, New Scientist, the Irish Times, EMBO Reports, Chemistry & Industry, and more. He is President of the Irish Science & Technology Journalists Association. 

    View Full Profile
Share
December digest cover image of a wooden sculpture comprised of multiple wooden neurons that form a seahorse.
December 2025, Issue 1

Wooden Neurons: An Artistic Vision of the Brain

A neurobiologist, who loves the morphology of cells, turns these shapes into works of art made from wood.

View this Issue
Stacks of cell culture dishes, plates, and flasks with pink cell culture medium on a white background.

Driving Innovation with Cell Culture Essentials

Merck
Stacks of cell culture dishes, plates, and flasks with pink cell culture medium on a white background.

Driving Innovation with Cell Culture Essentials

MilliporeSigma purple logo
Human iPSC-derived Models for Brain Disease Research

Human iPSC-derived Models for Neurodegenerative Disease Research

Fujifilm
Abstract wireframe sphere with colorful dots and connecting lines representing the complex cellular and molecular interactions within the tumor microenvironment.

Exploring the Inflammatory Tumor Microenvironment 

Cellecta logo

Products

brandtech logo

BRANDTECH® Scientific Announces Strategic Partnership with Copia Scientific to Strengthen Sales and Service of the BRAND® Liquid Handling Station (LHS) 

Top Innovations 2026 Contest Image

Enter Our 2026 Top Innovations Contest

Biotium Logo

Biotium Expands Tyramide Signal Amplification Portfolio with Brighter and More Stable Dyes for Enhanced Spatial Imaging

Labvantage Logo

LabVantage Solutions Awarded $22.3 Million U.S Customs and Border Protection Contract to Deliver Next-Generation Forensic LIMS