Plasma products can be treated by a variety of physical and chemical processes to inactivate viruses and thus to produce a product free from contamination and relatively safe for transfusion. Shortly after the development of the technology to manufacture AHF concentrate, it was recognized that these products carried a substantial risk of transmitting hepatitis B. Although some blood derivative products had been treated with heat to destroy live viruses since the late 1940s, Factor VIII and IX concentrates in the United States were not subject to viral inactivation procedures until 1983 and 1984. If this technology had been developed and introduced before 1980 to inactivate hepatitis B virus and non-A, non-B hepatitis virus, fewer individuals with hemophilia might have been infected with HIV.
Overall, the record of the plasma fractionators and the FDA with respect to the development and implementation of heat treatment is mixed. The Committee's analysis focused on whether the basic knowledge and technology for inactivating viruses in AHF concentrate had been available before 1980 and whether industry had appropriate incentives (from FDA, NIH, NHF, or others) to develop viral inactivation procedures. In the Committee's judgment, heat treatment processes to prevent the transmission of hepatitis, an advance that would have prevented many cases of AIDS in individuals with hemophilia, might have been developed before 1980. For a variety of reasons (e.g., concern about possible development of inhibitors and higher costs), however, neither physicians caring for individuals with hemophilia nor the Public Health Service agencies actively encouraged the plasma fractionation companies to develop heat treatment measures earlier. The absence of incentives, as well as the lack of a countervailing force to advocate blood product safety, contributed to the plasma fractionation industry's slow rate of progress toward the development of heat-treated products. Once plasma fractionators developed inactivation methods, however, the FDA moved expeditiously to license them.
The purpose of donor screening and deferral procedures is to minimize the possibility of transmitting an infectious agent from a unit of donated blood to the recipient of that unit, as well as to ensure the welfare of the donor. Donor screening includes the identification of suitable donors; the recruitment of donors; and the exclusion of high-risk individuals through methods and procedures used at the time of donation, such as questionnaires, interviews, medical exams, blood tests, and providing donors with the opportunity to self-