BCG Vaccination Delivers Disease Protection to Different People

Nearly 100 years old, the bacille Calmette-Guérin (BCG) vaccine continues offering disease protection. According to a recent study funded by the U.S. NIH, 'BCG vaccination at birth is effective at preventing tuberculosis (TB) in young children.

But BCG vaccination is ineffective when administered in adolescents and adults.

Therefore, TB immunoprotection needs to be boosted in older populations.

Published in The Lancet Global Health as an early release for September 2022 and led by BU School of Public Health researchers, this study offers new insight and clarity on the BCG vaccine's continued value. 

"Unlike many of the mRNA COVID-19 vaccines, which we know are highly effective, there is widespread debate on the BCG vaccine's effectiveness and duration of protection, as well as whether the vaccine only works in selective settings," says study lead author Leonardo Martinez, assistant professor of epidemiology, in a press release on August 9, 2022.

"Our findings indicate that BCG vaccination is effective at preventing tuberculosis in young children. However, since tuberculosis in children is a highly debilitating and severe disease, BCG vaccination should continue to be used."

Martinez added, "Novel vaccines are urgently needed to supplement BCG vaccination in high-burden settings."

These findings provide up-to-date assessments of BCG vaccine effectiveness against TB.

This new analysis presents data over the past ten years from high-burden settings in 17 countries, including South Africa, China, Vietnam, Indonesia, Uganda, The Gambia, and Brazil.

The BCG vaccine is seldom offered in the USA since TB was eradicated years ago.

In addition to TB, the BCG vaccine has been found effective against various diseases, such as meningitis and bladder cancer.