Ok. So it is your opinion that those who are certain to have had the virus don’t need to wear masks, and those who haven’t, should?
My understanding of the virus as of now:
It spreads best indoors when people are forcefully exhaling - like davening in shul and dancing at a wedding.
Outdoors spread seems to be minimal.
Masks trap droplets exhaled, so if a person is shedding virus, a mask will catch many of the germs.
Reinfection is still rare. I don't believe a word from the Chinese, but we don't see mass reinfection in any country whose infections were ahead of ours and whose peoples' antibody load has presumably dropped after a few months.
Lemaaseh:
-Anyone who hasn't had it yet should probably wear a mask in shul. Even though you feel like a dork. Because if you just caught it and are not yet symptomatic, the old / at risk man who's also in shul might be at risk from you.
-Anyone who hasn't had it yet who has risk factors should wear a mask in shul, stores and most public places.
With the uptick in cases recently, please be especially vigilant. Stay away from the public as much as possible.
Please note: Cloth masks do little but catch droplets. Surgical masks have more filtering ability, but are nowhere near 95% filtering. N95 masks are great for filtering, but not great for breathing while doing your regular life.