Tuberculosis vaccine: A journey from BCG to present

Area of Science:

• Immunology
• Infectious Diseases
• Vaccinology

Background:

• Tuberculosis (TB) is a leading global infectious cause of death, claiming 1.6 million lives annually.
• Drug-resistant Mycobacterium tuberculosis (M.tb) and HIV-TB co-infection complicate TB treatment and prognosis.
• The Bacille Calmette-Guerin (BCG) vaccine, the only licensed TB vaccine, has variable efficacy, particularly in adult pulmonary TB.

Purpose of the Study:

• To review the historical development of the BCG vaccine.
• To summarize the limitations of current TB vaccine strategies.
• To highlight recent advancements in TB vaccinology, including new vaccine candidates in clinical and pre-clinical trials.

Main Methods:

• Literature review of TB vaccine development.
• Analysis of BCG vaccine efficacy and limitations.
• Summary of emerging TB vaccine candidates and their trial status.

Main Results:

• BCG vaccine provides variable protection, mainly against childhood TB, but is ineffective in adult pulmonary TB.
• Numerous novel vaccine candidates are in development to replace or boost BCG.
• These new candidates aim to address limitations of BCG and combat drug-resistant TB.

Conclusions:

• There is a critical need for more effective TB vaccines.
• Ongoing research and clinical trials show promise for future TB vaccinology.
• New vaccines could significantly improve the global TB control program.