PREVALENCE OF INFECTION WITH THE HEPATITIS-C VIRUS AMONG ITALIAN HEMOPHILIACS BEFORE AND AFTER THE INTRODUCTION OF VIRALLY INACTIVATED CLOTTING FACTOR CONCENTRATES - A RETROSPECTIVE EVALUATION

In July 1985, all coagulation factor concentrates were withdrawn from the market in Italy and replaced with virally inactivated concentrates . A retrospective survey comparing the prevalence of the antibody to t he hepatitis C virus (anti-HCV) in hemophiliacs multitransfused with n onvirally inactivated concentrates until 1985 with that in previously untreated hemophiliacs transfused exclusively with virally inactivated concentrates since 1985 has been conducted in 9 Italian hemophilia ce nters. The centers, which follow about one-fourth of all the Italian h emophiliacs, provided information about 708 patients infused for the f irst time before 1985 (group A) and 80 patients infused for the first time between 1985 and 1991 (group B). The prevalence of anti-HCV was 8 3% (591/708) in group A and 6% (5/80) in group B. For the 5 anti-HCV-s eropositive patients from group B, dry heating, hydrophobic interactio n chromatography plus dry heating (2 patients), hot vapor and pasteuri zation were the virucidal methods used for the concentrates implicated in HCV transmission. In the case associated with pasteurization, ther e is the possibility of intrafamilial transmission of HCV. It appears from this retrospective analysis that there has been a substantial red uction in the risk of HCV transmission since the adoption of virucidal methods. However, these methods do not eliminate completely the risk, which might be further reduced by the recent adoption of anti-HCV scr eening for plasma donations used to manufacture concentrates.