Why do some people say they always get sick after getting the flu shot?
This may be true, but for a very small number of people, says Duke infectious disease expert Dr. Cameron Wolfe.
The vaccine is quite good at building your immunity, so some people with a robust immune system will respond more vigorously to the vaccine building their immunity, but feeling a little worse while that occurs.
A sore shoulder, low-grade temperatures, and mild aches are possible for about 5 to 10 percent of the adult population.
Remember, it’s building your immunity, so it’s a protective response. The vaccine will not give you the flu.