Prevalences of TTV and HCV infections and GBV-C/HGV exposure. Includes characteristics of 173 multiple-transfused patients (according to the number of blood-donor exposures). GBV-C/HGV exposure includes individuals positive for viral RNA and/or anti-E2 antibody. The prevalence was significantly related to the blood-donor exposure for all 3 viruses (P < .001). However, for TTV, the significant overall difference was mainly due to the difference between the group with greater than 100 PRC versus each of the 2 other groups.