They also wear surgical masks.
Which means, these masks are made for and used during surgeries.
Not to protect anyone from Viruses that would be beyond idiotic.
But to protect contamination of the open wound of the patient.

Also they have very strict procedures how they handle the masks, which are certified medical devices that come in sterile packaging.
They put them in with the help of a nurse. Because it’s almost impossible to put one on without help end not contaminate it by touching it.
They have also nurses ready to adjust or change the mask at any time - and they have protocol to change it every 15-20 minutes