Donor deferral requirements and lookback procedures are described in CFR Title 21 Part 610. Section 610.41 discusses donor deferral requirements and sections 610.46–610.47 describe "lookback" procedures.
When a donor tests positive for an infectious disease, the recipients of blood components from previous donations are identified, notified, and, whenever possible, tested to determine if they are positive for the transfusion transmissible disease. If a donor is confirmed positive for HIV, section 610.46 applies. Section 610.47 contains the requirements for notification of the recipients when the donor tests positive for hepatitis C virus (HCV).
These sections outline the time frames for the patient's physician and recipient notifications.
From the transfusion service perspective, the major difference in the lookback process is that in the case of HIV, the relatives must be notified in the event the recipient is deceased.