BCG vaccine may rewire brain immunity, shift Alzheimer's markers over 12 months

New research led by Mass General Brigham investigators suggests that the Bacillus Calmette-Guérin (BCG) vaccine—which is delivered through the skin to prevent tuberculosis—may remodel the human brain's immune environment, offering a potential biological explanation for previously observed associations between BCG vaccination and lower Alzheimer's disease risk. Findings are published in Communications Medicine.