Flu vaccination linked to 40% reduced risk of Alzheimer’s disease

The correlation is probably loosely causative based on other research pointing to certain infections preceding a descent into Alzheimer's or Dementia.

Related (not exhaustive. The infectious theory is rapidly gaining ground especially in light of anti-beta-amyloid drugs repeatedly failing in clinical trials):

* HSV/Alzheimer's: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8234998/

* HSV/Alzheimer's: https://content.iospress.com/articles/journal-of-alzheimers-...

* HSV/Alzheimer's: https://pubmed.ncbi.nlm.nih.gov/29488144/ (current independent phase 2 trial to reproduce outcomes: https://clinicaltrials.gov/ct2/show/NCT03282916)

* Gingivitis/Alzheimer's: https://pubmed.ncbi.nlm.nih.gov/32280099/

* Immunological role of Beta-Amyloid: https://alz-journals.onlinelibrary.wiley.com/doi/full/10.100...

And not just flu, HSV and gingivitis.

Tdap vaccination is also apparently protective. So, probably too chicken pox vaccination, shingles vaccination, and periodic valacyclovir dosage. Maybe even HPV.

You don't need very good reasons to keep up on your vaccinations.