Thankfully my blood pressure returned to it's normal 100/70. FINALLY. After about a year of being elevated.
It too is adjusted every year toWell, I call the flu shot a flu shot.
deal with newly evolved strains.
Diseases are a moving target.
What is a vaccine?
Vaccine - Wikipedia
en.wikipedia.org
A vaccine is a biological preparation that provides active acquired immunity to a particular infectious or malignant disease.
Note that having to "adjust" it yearly doesn't defeat
the definition.