Regardless of immunization status, if you have COVID-19, you should stay at home for at least five days to isolate from others and then wear a mask for an additional five days while going out in public.
If you have symptoms and think you may have COVID-19 but haven’t had test results yet, you should also isolate yourself. You should take two tests separated by 48 hours if your findings are negative. It’s conceivable that you have COVID-19 even though your original test did not detect it. If the results of both tests are negative, you can end your isolation.
If it is discovered that you have COVID-19, you should start wearing a high-quality mask or respirator (such as a N95) whenever you are among people, whether it be within your house or in a public place that is inside. For ten whole days, wear a mask; do not venture somewhere where you cannot. There is no reason for you to stay at home if you don’t have symptoms or if they don’t appear (quarantine). If you have signs of COVID-19, such as fever, coughing, shortness of breath, or other symptoms, isolate yourself at home right once, get tested, and remain there until you get the results.
In China, experts made similar suggestions at the end of 2002. Wear KN95 or N95 masks when the transmission rate and disease rate are high. After infection, people should be isolated at home and have a good rest. After recovery, when you go out, you would better wear N95 mask to prevent infecting covid virus again.