My understanding is that for about 3 months after someone has recovered from COVID they are considered immune for getting it again. After 3 months there have been reported cases of people getting infected again. It’s pretty rare though. It’s generally thought that after COVID symptoms start one is no longer contagious after 10 days as long as symptoms are improving and there have been no fevers for 24 hours without using any fever reducing medication. That’s the CDC recommendation for isolation and the recommendation I’ve been providing to hundreds of patient’s I’ve been caring for with confirmed COVID or suspected COVID.
My husband is a physician scientist and that is his understanding of how the virus works too according to the CDC. But the scientist in him thinks it is still too early to conclude that IS how the virus works. So he has been recommending his patients and staff to isolate for at least 14 days, don’t assume you are not contagious, get tested and even with a negative test, isolate for an additional 7-14 days and test again, before thinking you are safe for yourself and for others around you. And continue to keep that mask on, stay away from others and wash your hands. Not pick and choose, but all 3 goes hand in hand. The virus does not discriminate, nor is anyone guaranteed immunity. It’s better to be safe than sorry.