Hepatitis C virus infection in asymptomatic male volunteer blood donors in Karachi, Pakistan.

The objectives of this study were to assess the proportion of hepatitis C virus (HCV) reactors and to identify risk factors associated with HCV infection in volunteer blood donors in Karachi, Pakistan. Between 1 January 1998 and 31 December 2002, consecutive blood donations tested at two blood banks were used to assess the proportion of HCV sero-reactors donors. To evaluate the potential risk factors, a case-control study design was implemented to select cases and controls between 15 October 2001 and 15 March 2002. The overall seroprevalence of HCV in these blood donors was 1.8% (6349/35 1309). Trend analysis revealed a significant (P < 0.001) linear increase in proportions of HCV-seropositive donors from 1998 to 2002. Final multivariate logistic regression model showed that the cases were more likely than controls to have reported past hospitalization or to have received multiple injections. When a glass syringe was used to give therapeutic injections, it increased the adjusted odds of being HCV seropositive significantly more among cases than in controls and this relationship was stronger when injection was given by general medical practitioner than if the injection was given in hospital setting. Cases were more likely than controls to have reported sexual contact with multiple sexual partners. Primary prevention programmes focused on identified risk factors might help to curtail the spread of HCV infection in this community and in other similar settings in developing countries.