BCG vaccine

American  

noun

Immunology.

1. a vaccine made from weakened strains of tubercle bacilli, used to produce immunity against tuberculosis.

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BCG vaccine Scientific  

/ bē′sē-jē′ /

1. A preparation used to immunize individuals against tuberculosis, consisting of attenuated live human tubercle bacilli (Mycobacterium tuberculosis), the bacteria that cause tuberculosis.

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Etymology

Origin of BCG vaccine

1925–30; B(acillus) C(almette-)G(uérin)

Example Sentences

The BCG vaccine given to newborns in many parts of the developing world to prevent tuberculosis also seems to have a systemic immune response that helps prevent infant mortality from other infections, says Topham.

From The Wall Street Journal • Dec. 6, 2025

Indeed, there’s evidence to suggest it may have been a mistake to stop administering the smallpox vaccine after the total elimination of smallpox, or to end the BCG vaccine as tuberculosis infection became rare.

From Salon • Jul. 12, 2025

"The BCG vaccine offers the prospect of near-lifelong protection against every variant of COVID-19, the flu, respiratory syncytial virus, and other infectious diseases," said Faustman.

From Science Daily • May 22, 2024

Experts also point out that a 17-year-long BCG vaccine trial held between 1968 and 1987 - involving more than 280,000 people in Tamil Nadu state - ended with disappointing results.

From BBC • Jan. 3, 2024

The most widely used vaccine in history, with more than 4 billion doses given to patients since 1921, the BCG vaccine contains a live but weakened version of the TB bacteria.

From Science Daily • Nov. 29, 2023