SUMMARYThe introduction of screening for hepatitis C virus (HCV) by the National Blood Transfusion Service identified donors who had acquired HCV infection. We undertook a case-control study amongst blood donors in the Trent Region to determine risks for HCV infection. A total of 74 blood donors confirmed positive for hepatitis C infection and 150 age, sex and donor venue matched controls were included in the study. Fifty-three percent of hepatitis C infected blood donors reported previous use of injected drugs compared to no controls; relative risk (RR) not estimatable (lower limit 95% CI = 20). Other risk factors were a history of: receipt of a blood transfusion or blood products RR = 3·6 (95% CI 1·5–8·3), having been a ‘health care worker’ RR = 2·8 (95% CI 1·1–7·6), tattooing RR = 3·3 (95% CI 1·2–8·7), and an association with having been born abroad RR = 3·2 (95% CI 1·1–9·5). No risk was shown for a history of multiple sexual partners, ear piercing or acupuncture. Injecting drug use explains more than 50% of hepatitis C infections in blood donors, a group who are less likely to have injected drugs than the general population.
Risk factors for hepatitis C virus infection among blood donors in southern Brazil: a case-control study