To protect the patients from bacteria....etc. Nobody say masks are completely useless just not that protective against a virus smaller than the masks ability to filter.
its actually as simple as Moisture droplets ( 5 microns) , and the size of the Virus ( .3 Microns) which is much smaller than moisture droplets , but it is inside the moisture being breathed out, and then in.
Doctors and Nurses DO protect themselves with
1)- a PROFESSIONAL Mask N95 or better
2)- worn Properly...
3)- worn 100% of the time when in work situation
ie. they protect themselves .. others are not protecting them with THEIR Idiotic Masks worn in Idiotic ways ..
99 % wear a mask incorrectly, and most everyone in the general population is part of that 99 %
The Doctors and Professional are ALL within that 1 % who wear the right mask, and wear it Properly ..
u just cant explain this stuff to some people here ,as the comments clearly show ..