“A mask should do”?

If someone cannot receive the vaccine due to

allergy to one or more components, or

immune suppression, as chemo for cancer does as well as treatment for autoimmune disorders like multiple sclerosis.

IIRC the state of Rhode Island requires choice of either a flu shot or wearing of a mask. A nurse, when this law was newer, got fired due to refusal to do either.

And health care workers like nurses, physicians, physical therapists etc. having a lot of close contact with patients should be required to either get a vaccine or wear a mask. They aren’t workers with only brief in person contact, but, especially in institutional settings, are spending more time with patients, including those more likely to experience poor outcome from flu & COVID 19.