Blood donors with 'medium' or 'minor' risk factors for human immunodeficiency virus infection: Are they eligible for donation?

Background and Objectives. We conducted a longitudinal prospective study to assess the eligibility to blood donation of donors with 'minor' risk factors (i.e. minor surgery, professional exposure, cohabitation with 'high risk' people, occasional use of light drugs) or 'medium' risk factors for human immunodeficiency virus (HIV) infection (i.e. casual sexual relationships, multiple heterosexual exposures, sexual partnership with subjects at risk, regular use of light drugs). Design and Methods. During a 4-year period we administered a psychosocial questionnaire to all donors attending our Center. In addition we determined anti-HIV, anti-hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg) and syphilis serology (TPHA) at entry to the study and at 6-month intervals. Results. Of 25,367 donors, 1,535 (6%) reported medium and 8,761 (34%) minor risk. At enrollment into the study, 4 medium risk donors were anti-HIV positive and there was a significantly higher rate of positivity for TPHA (0.33% vs 0.07%) and anti-HCV (1.17% vs 0.63%) in this group than in donors reporting no risk. No anti-HIV positivity was observed in minor or no risk donors. During a median follow-up of 18 months, none of 24,404 donors undergoing 106,503 visits seroconverted to HIV. The incidences of new HCV and syphilis infections were almost one log greater in donors at medium risk (3 and 1x10^-4/yr, respectively) than in no risk donors (0.4 and O.1x10^-4/yr, respectively). Medium risk donors were more frequently males (Odds Ratio=3.2, 95% confidence interval= 2.8-3.7), aged 26-35 yrs (1.52; 1.3-1.78), single (1.4; 1.2-1.6), divorced (2; 1.4-2.8), freelance workers (1.43; 1.1-1.9) and first-time donors (1.8; 1.6-2.1) than no risk donors. Interpretation and Conclusions. The only 4 HIV positive subjects of the cohort were medium risk donors picked up at enrollment. No HIV seroconversion was observed during the study. On the basis of this study we will continue to defer 'medium' risk donors. (C) 2000, Ferrata Storti Foundation.