E-Mail UNIVERSITY PARK, Pa. -- The optimal timeframe for donating convalescent plasma for use in COVID-19 immunotherapy, which was given emergency use authorization by the Food and Drug Administration in August 2020, is within 60 days of the onset of symptoms, according to a new Penn State-led study. The research also reveals that the ideal convalescent plasma donor is a recovered COVID-19 patient who is older than 30 and whose illness had been severe. "Millions of individuals worldwide have recovered from COVID-19 and may be eligible for participation in convalescent plasma donor programs," said Vivek Kapur, professor of microbiology and infectious diseases, Penn State. "Our findings enable identification of the most promising donors and suggest that these people should donate quickly before their antibodies begin to wane."