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

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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 ...

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  • 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. 

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