Always a few

Please note that the more medically educated, the more likely to get the vaccine. That's why you see LPNs happily refusing vaccine, while almost all physicians have gotten it.

However, you'll always have a few radicalized in any population. Medicine is a stressful job and it affects mental health more than most jobs. Some doctors (and ER docs are over represented in this category) think they know better than everyone else. Doctors in general are very hard to get to agree on anything, so the fact that 90+% of doctors signed up for the vaccine is a stunning support of the vaccine.