if you are carrying c-19 (whether or not you have symptoms) and bite your fingernails or whatever and then touch a few public door knobs, you could infect potentially thousands of people.
so wash your hands after you touch your face and before you touch the doorknob.
if you touch a virus-y public doorknob and later bite your fingernails, you might infect yourself.
so wash your hands after you touch the doorknob and before you touch your face.
Got it, the virus touching your hands themselves from your own holes or from some 3rd party isn't problematic, presuming you promptly wash it off. Hands are just a virus vessel getting it from or to a problematic intake hole.
And definitely don't show off that you can open a door by using your mouf to turn the doorknob.