Plasma therapy for Covid-19: States to begin clinical trial

According to Johns Hopkins University, plasma therapy has been used since the 1890s to "combat diseases as wide-ranging as measles, Ebola, H1N1 flu and polio."

The University also refers to an 80-person trial in Hong Kong during the SARS outbreak in 2002-2003 which found that people treated with it within two weeks of symptoms were more likely to get discharged.