A response to: Self-reported and actual hepatitis C virus infection status

Sir—We thank our correspondents for their response to our paper, and wish to highlight several points in reply.

We agree that the concordance between a person's actual and perceived hepatitis C virus (HCV) status may be influenced by multiple factors, educational background being one. Concordance may also be affected by the characteristics of different diseases and by the health environments in which those diseases exist. Hepatitis B virus (HBV) is a more complex virus to diagnose and explain than HCV, and so we find it unsurprising that our rates of HCV concordance are higher than the HBV concordance in relatively low-risk first-year Thai medical students. Previous studies have found similarly low levels of concordance for HBV in people who inject drugs (PWID) [1].

We agree with our correspondents that high rates of HCV concordance among PWID should not be used to replace testing with self-report. Our data suggest 20% of Australian PWID do not know their HCV status, and thus are at risk of unknowingly transmitting or acquiring HCV. There is no substitute for widespread availability of free sero-testing and comprehensive and accurate post-test discussions. Our work in the HCV field over more than two decades shows that voluntary blood-borne virus testing outside of traditional settings is acceptable to PWID and that this can improve knowledge and reduce risk taking [2, 3].