Hepatitis C – commonly asked questions

Abstract

The overall figures of the incidence of hepatitis C virus (HCV) infection in Australia are very high. Are we still seeing a high incidence of HCV in the existing population? There is no easy way of separating what we call prevalence from incidence of disease. Most of the people we are picking up are chronically infected individuals who may have been infected a year or 20 years ago. The tests don't tell us when infection occurred. Occasionally, we see people who have clearly recently seroconverted, but that is unusual. Therefore, most of the disease we detect is prevalent disease, potentially acquired over a long period of time. This does tell us the total disease burden in the community but not the rate at which it is increasing. However, cohort studies show us that people within the high-risk groups, particularly the intravenous drug users, are continuing to acquire infection. We also know that interventions, such as the needle exchange programs, can reduce the incidence of acquisition of HCV in those groups.