Opinion: We don’t know if convalescent plasma is effective against Covid-19. With the emergency authorization, we might never know
Convalescent plasma has been used to fight many infectious diseases, from scarlet fever in the 1930s to whooping cough and measles and, in more recent times, swine flu, Ebola, and Middle East respiratory syndrome.
The idea seems to make sense: The plasma of people who survive these diseases contains antibodies that may have helped them survive. When their plasma is donated and the antibodies are isolated from it and transfused, it could perhaps help newly infected people survive as well.
