“…Prior to 1995, one blood donation in every 210,000 to 1,140,000 in the United States was estimated to be from an HIV-infected individual during the window period, which is usually 22 to 25 days or longer (17). By implementing antigen screening of blood, an estimated four to six cases of transfusion-associated HIV infections may be prevented per year, lowering the estimated risk per unit transfused to a range of one in 562,000 to one in 825,000 (9,17). Therefore, it appears that antigen testing has utility for helping to protect the blood supply, though at a cost exceeding $60 million annually.…”