Blood donors and the challenges in supplying blood products and factor concentrates.

Voluntary blood donors are the source of all red cell, platelet, and unprocessed plasma products used in clinical medicine. Paid donors provide most of the raw plasma used in commercially processed plasma products, such as albumin and intravenous gamma globulin. Each year, less than 5% of the population donates blood, and almost half the units come from 1% of the population who are frequent donors. Pressures that affect the number of potential donors include changing demography and motivation. Pressures that affect the suitability of potential donors include endemic and emerging infectious diseases, drug and vaccine use, and behavioral factors. The net result of these pressures is increasing difficulty in finding enough acceptable donors. Demands on the current blood supply leave few resources and raw materials available for the development of newer, safer, and more effective therapeutic products. The development of recombinant coagulation proteins reduces the pressure on this limited supply of donated plasma, and reducing bleeding protects the supply of cellular blood and plasma-derived products.