When reaching age 50+, immune system undergoes dramatic aging-related changes. Boost up immunity in the elderly to prevent infections and reduce disease severity with essential vaccines:
A threat to your heart and blood vessels
What is the difference between a higher-dose flu vaccine and 4-strain flu vaccine?
Why do you need flu vaccine every year
Strengthening the immunity and beautifying senior life
Prevent yourself from rabies with rabies vaccine (pre-exposure prophylaxis)