A colleague of mine has been asked to leave by the GP simply because she's not wearing a mask. When confronted, the GP's reasoning was simply a precautionary measure and asked to come back when she's ready.
She was absolutely gobsmacked.
What kind of world do we live in right now when a GP refused to treat an ill patient?
Is your colleague Asian looking? It's part racism, part paranoia, part policy. Re: policy. People at several places (especially in China) are told to stay home if they have flu symptoms. GP refusing to see a person for not wearing a mask is unlikely.
What symptoms does your "friend" have?