People who had COVID-19 and are now fully recovered may be eligible to donate plasma to help patients currently infected with COVID-19. Their plasma likely contains antibodies that bind and inhibit SARS-CoV-2, the novel coronavirus that causes COVID-19.
The American Red Cross requires donors to be at least 17 years of age and weigh 110 pounds. Donors who are 17 or 18 have additional weight requirements.
Donors also have to have antibodies that are at a high enough concentration to be helpful for patients. The Food and Drug Administration recommends donors have a SARS-CoV-2 neutralizing antibody titer of 1:160, meaning the antibodies can still be detected even after diluting the sample down to 160th of its original concentration. The agency notes that a titer of 1:80 is acceptable if there aren't any other donated plasma samples with the appropriate blood type available.