Vaccines targeting adults, teens best chance to eliminate TB

Targets to eliminate tuberculosis (TB) by 2050 are more likely to be met if new vaccines are developed for adults and adolescents rather than infants, according to a new research.
Researchers at the London School of Hygiene & Tropical Medicine and the Stop TB Department at the World Health Organisation found that a vaccine given to adolescents and adults in low- and middle-income countries could have a much larger impact on the burden of TB worldwide and is more likely to be cost-effective, even if the vaccine has low efficacy and short duration or carries a high price.
TB mostly affects young adults and kills more than one million people every year, 95 per cent of whom are in low- and middle-income countries. The World Health Organisation has set the goal of eliminating TB by the year 2050.

The researchers used a mathematical model to estimate the impact and cost-effectiveness of a range of vaccination strategies in low- and middle-income countries.
Assuming these vaccines become available in 2024, they identified which strategy would have the greatest impact on TB worldwide over the years 2024 to 2050.
"Dramatic levels of control are needed to eliminate TB and new vaccines need to be developed now. But because trials of TB vaccines are hugely expensive, their development needs very clear guidance," said lead author Gwen Knight, research fellow in infectious disease modelling at the London School of Hygiene & Tropical Medicine.

"If elimination by 2050 is the goal, our study provides evidence that new vaccines should focus on targeting adolescents and adults rather than children," Knight said.

The current TB vaccine, bacille Calmette-Guerin (BCG), is widely given to infants. But despite this, TB cases and deaths remain extremely high.
Previous studies have suggested that TB elimination can only be achieved through the use of new vaccines.
The new study was published in the journal Proceedings of the National Academy of Sciences.