Dear n0mesorah
If someone was tested positive for coronavirus C”V the person has to immediately do his/her hishtadlus required for that situation which for Covid-19 requires a person to completely go into quarantine and stay away from people to prevent the sickness from spreading out to others until the person does his spiritual part of hishtadlus of tefilla begging Hashem to send him a refuah shleima ASAP so s/he can go back out like normal and serve Hashem with all the mitzvos.
This is why you will definitely see more older people versus younger people wearing masks. The coronavirus is more of a risk for older people then young adults or kids etc…. And they are all doing their hishtadlus required by wearing masks and some still davening outside minyan even though they can really daven inside a shul
May everyone stay safe and healthy and always put safety first. BETTER SAFE THAN SORRY.