Lapsed donors: an untapped resource.

Background: There is a clear need for methods to recruit and retain donors without compromising blood safety. Although prior studies report lower viral prevalence rates in repeat donors than those in first-time donors, it is unknown if this relationship holds after a lapse of several years between donations.

Study Design And Methods: A total of 6.4 million allogeneic donations collected at five US blood centers from 1991 through 1998 were classified by donation history (first-time vs. repeat) and by length of time between donations (lapsed interval length). The prevalence of HCV, HIV, and HBsAg was compared by donation history and lapsed interval length. The relationship between lapsed interval length and donor demographics was explored.

Results: Repeat donors who delayed their return for over 5 years were significantly less likely to test positive for a viral infection than were first-time donors. The likelihood of a positive test result appeared to increase steadily with lapsed interval length for HCV and HBsAg, but not for HIV. Younger, less educated, and nonwhite donors were less likely to return than others.

Conclusions: Recruitment of donors who have not returned for several years could be an effective way to increase the blood supply while preserving blood safety. Understanding the relationship of donor demographics to return behavior is important for recruitment efforts.