Flow chart showing the breakdown of American Red Cross HBV-infected blood donors and study participation, June 2009 to April 2015. * Viral load was obtained from 1248 (34%) prevalent, 43 (90%) HBV DNA yield, 51 (71%) HBsAg yield, and 201 (34%) OBI donors. HBV, hepatitis B virus; OBI, occult hepatitis B infection; RBI, recent hepatitis B infection.