We tested 70 blood donors from Fortaleza (Ceara state, Brazil) for GB virus C/hepatitis G virus (GBV/HGV) infection by polymerase chain reaction and detection of antienvelope antibodies. Twenty-seven (38.6%) showed signs of an active or resolved infection. Sixty-four percent of those with indications of other blood-borne viral infections showed signs of GBV-C/HGV infection also.
Goubau, P., Andrade, F. B., Liu, H. F., Basilio, F. P., Croonen, L., & Barreto-Gomes, V. A. (1999). Prevalence of GB virus C/hepatitis G virus among blood donors in north-eastern Brazil. Tropical Medicine & International Health, 4(5), 365-367. https://doi.org/10.1046/j.1365-3156.1999.00407.x (Original work published 1999)