In the UK, there have been few studies of the seroprevalence of antibodies
to hepatitis C virus (anti-HCV). As part of an ongoing prevalence study of
HCV in injecting drug users, we have developed a technique for detecting an
ti-HCV in blood spots dried on filter paper using a commercially available
assay. Subjects with and without serum anti-HCV were studied. The manufactu
rer's recommended cut-off (CO) for a positive anti-HCV result is kit-depend
ent, and therefore a ratio of test result (T) to kit CO was used to standar
dize results. T/CO values greater than 0.99 had a sensitivity of 100% and a
specificity of 87.5% for anti-HCV detection. T/CO values greater than 1.99
had a sensitivity of 97.2% and a specificity of 100%. Hence, testing dried
blood spots may be useful for detecting anti-HCV in epidemiological studie
s and as a diagnostic test in patients with poor peripheral venous access.