A study of anti-hepatitis C positive blood donors: the first year of screening

SUMMARY. In the U.K., blood donations have been routinely screened for anti-HCV since September 1991. In order to get the most epidemiological benefit from these extensive screening data, the histories obtained at counselling from donors confirmed to be anti-HCV positive, 'indeterminate' and falsely positive have been analysed in detail. In addition, the associations with potential risk factors have been investigated by comparing these groups of donors with a control group of 771 routine donors bled on one day during the study, at North London Blood Transfusion Centre. This paper documents the prevalence and demography of HCV infection in asymptomatic blood donors, to assess varicus possible sources of infection and the association between liver function test results and alcohol consumption in donors. One in 1400 previously untested donors was confirmed positive for anti-HCV. Age (the group 30–49 years being highest), tattooing and intravenous drug use in both sexes, ear-piercing in males and blood transfusion in females were all significantly associated with an increased risk of HCV infection. Intravenous drug use proved to be the factor most strongly associated with risk. Liver function tests (alanine aminotransferase) were elevated in a significant number of donors confirmed to be anti-HCV positive but no clear correlation between alanine aminotransferase level and either time since infection or alcohol consumption was found. Alcohol consumption was significantly higher in donors confirmed to be anti-HCV positive and was particularly marked in those admitting to previous intravenous drug use. Although donors confirmed to be anti-HCV positive had a 5–10 times greater chance of non-Caucasian ethnic origin compared with controls, the association with ethnic origin was not as marked as it was for HBsAg positive donors.