Can blood from coronavirus survivors help other people fight the illness?... Doctors in New York will soon be testing the idea in hospitalized patients who are seriously ill. Blood from people who have recovered can be a rich source of antibodies, proteins made by the immune system to attack the virus.... The part of the blood that contains antibodies, so-called convalescent plasma, has been used for decades to treat infectious diseases, including Ebola and influenza.“ It’s kind of difficult s