Daijiworld Media Network – Washington
Washington, Sep 26: Vaccines do more than protect against infectious diseases — growing research suggests some also reduce the risk of dementia.
“Preventing severe infections, especially in older adults, is huge. But there seems to also be some kind of added benefit,” said Avram Bukhbinder, a resident physician at Massachusetts General Hospital who studies vaccines and dementia risk.
Vaccines with strongest links
• Flu shot: Influenza and pneumonia are tied to five neurodegenerative diseases, including dementia. A 2022 study of 1.8 million U.S. adults over 65 found those who received at least one flu vaccine were 40 % less likely to develop Alzheimer’s within four years. A 2024 study linked the shot to a 17 % lower dementia risk.
• Shingles vaccine: Multiple large studies, including a 2025 analysis of 280,000 adults in Wales, show about a 20 % reduction in dementia risk. Researchers believe the varicella-zoster virus, which causes shingles, can directly affect the brain.
• RSV vaccine: Approved in 2023, it protects older adults from respiratory syncytial virus. A recent study of 430,000 people found RSV vaccination, like shingles shots, was tied to reduced dementia risk.
• Tdap vaccine: Shots against tetanus, diphtheria and pertussis are also associated with lower dementia rates, especially when combined with the shingles vaccine.
Why the link?
Severe infections can trigger systemic inflammation that accelerates brain atrophy, pushing those with underlying Alzheimer’s or other dementia pathology “over the edge,” Bukhbinder said. Vaccines may help by preventing infections or by priming the immune system in beneficial ways.
Recommendations
The CDC advises:
• Annual flu shots for everyone over 6 months.
• Two doses of the shingles vaccine for adults 50+ or those with weakened immunity.
• RSV vaccination for adults 75+ and those over 50 at higher risk.
• A Tdap booster every 10 years for adults.
Experts caution the research is observational and not proof of direct causation, but the evidence adds “a more compelling reason” to stay current on vaccinations. Lifestyle measures — healthy blood pressure, social connection, limited alcohol, and addressing hearing loss — could prevent or delay up to 45 % of dementia cases, the 2024 Lancet Commission reports.