My wife and I both, still get the shots, back when I was still working, 15 years ago it was suggested that we [firefighters ] get the shot as we went to many medical calls and you never knew what you were in contact with[illnesses], It wasn't mandatory, but several of the guys that didn't get the flu shot , that I worked with did get the flu periodically over the years.
So after retirement , still get the shots and luckily neither of us have yet to get the flu.