My wife & I are both 90; we have had only one flu shot in the past & have escaped the flu. Is it advisable to continue without it?

Last year (2018) in the U.S. alone 80,000 people died of the flu. I'm not sure what you think the downside of getting the shot is... but please consider what the downside of NOT getting the shot may be.

https://www.statnews.com/2018/09/26/cdc-us-flu-deaths-winter/

I would recommend having the shot every year. Getting the flu in your 90's could have severe complications and it would be much more difficult to recover from than for a younger person. I hope you decide to get your shot.

I’d advise having the flu shot. It could save you from illness, one that could get very complicated, and there are no real bad effects. Glad you’re both doing so well, here’s to continuing!

Continue with your annual flu shots! It can't hurt and it may well save your life, particularly the older you get.

The flu doesn't care how fit you are or the good foods you eat. Please get your shots.