Why would we put peoples plasma into our own body to help build up our defense even though we don’t possibly have this virus? When we get a virus or disease or immune system is just going to automatically react to it it should be able to fight it off.
but plasma is only given to people who have COVID-19 and are having real difficulties. It would never be given to someone who was not really sick. Think of it as a quick fix while the body develops its' own antibodies.