Trends in incidence and prevalence of major transfusion-transmissible viral infections in US blood donors, 1991 to 1996. Retrovirus Epidemiology Donor Study (REDS)

CONTEXT: Evaluating trends in blood donor infectious disease rates is essential for monitoring blood supply safety and donor screening effectiveness. OBJECTIVE: To determine changes over time in blood donor population infection rates of human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV), hepatitis C virus (HCV), and hepatitis B virus (HBV). DESIGN: Cross-sectional survey data from the National Heart, Lung, and Blood Institute-sponsored Retrovirus Epidemiology Donor Study. SETTING: Five blood centers in different regions of the United States. PARTICIPANTS: A total of 1.9 million volunteer blood donors with 1 or more nonautologous donations from January 1991 to December 1996. MAIN OUTCOME MEASURES: Changes in rates of HIV, HTLV, HCV, and HBV infections were evaluated by comparing yearly prevalence estimates (per 100,000 donations) for first-time allogeneic donors and period-specific incidence rates (IRs) (per 100,000 person-years) for repeat allogeneic donors between 1991 and 1996 (for HCV, from about March 1992 to June 1996). RESULTS: Prevalence of HIV decreased in first-time donors from 0.030% to 0.015% (P=.006) and HCV prevalence decreased from 0.63% to 0.40% (P<.001). Trends were not statistically significant for the proportion of first-time donors with hepatitis B surface antigen (HBsAg) or HTLV. For repeat donors, IRs did not change significantly, indicating a stable but low level of seroconversion. The overall IRs (95% confidence intervals) per 100,000 person-years were 2.92 (2.26-3.70) for HIV, 1.59 (1.12-2.19) for HTLV, 3.25 (2.36-4.36) for HCV, and an estimated 10.43 (7.99-13. 37) for HBV (based on an HBsAg rate of 2.66 2.04-3.41] with presumed false-positive results considered negative). The HBV IR estimate with presumed false-positive results considered positive (for comparability to previous analyses) was 17.83 (14.60-21.56). CONCLUSION: The decrease in HIV and HCV prevalence rates, combined with the previously documented lower rates of infection in first-time donors compared with the general population, suggests the continued benefit of behavioral risk factor screening. JAMA. 2000;284:229-235