In 1921, the Bacillus Calmette–Guérin (BCG) vaccine was first used medically as a vaccine against tuberculosis. Primarily used outside of the United States, it remains on the World Health Organization's List of Essential Medicines and is given to hundreds of millions of children around the world each year.
The BCG vaccine works very well to prevent TB meningitis in children, so it prevents the most devastating form of TB, but it is less effective for other forms of TB. Outside of the US, TB is a real problem for children and adults. Not a perfect vaccine, but useful and recommended.
This vaccine has significant side effects, so it was phased out in the U.S. where TB is uncommon. For use in this country, the side effects of the BCG vaccine outweigh any benefits.
The BCG vaccine received a fair amount of attention last year when some research studies raised the possibility that it could be used against COVID-19.
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Ross McKinney, MD
Chief Scientific Officer
Association of American Medical Colleges
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