[Epidemiological information obtained from anti-hepatitis C virus screening in blood donors and candidates for autologous transfusion from 1992 to 1996 in the Alpes-Maritimes region]

Abstract

Objectives: To determine the evolution of the frequency of anti-hepatitis C virus antibodies from 1992 to 1996 in blood donors and in candidates for autologous transfusion in the Alpes-Maritimes region and to assess risk factors.

Methods: Anti-hepatitis C virus antibodies were assessed by second generation ELISA in 1992 and in the first quarter of 1993, and then by third generation ELISA; in all cases, anti-hepatitis C virus antibodies were confirmed by RIBA test.

Results: Since 1992 (when the second generation ELISA test became available), the prevalence of anti-hepatitis C virus antibodies in blood donors in the Alpes-Maritimes region (0.54% in 1992 to 0.20% in 1996) has decreased. Positive ELISA anti-hepatitis C virus was confirmed by RIBA in 53 to 68% of anti-hepatitis C virus blood donations. The percentage of anti-hepatitis C virus donors with ALT above the upper limit (donation exclusion threshold) was between 28 and 56%.The most frequent age interval for new anti-hepatitis C virus positive donors was between 30 and 40 years. Since 1992, a third of the anti-hepatitis C virus blood donors agreed to participate in a medical history questionnaire. One or several risk factors were found in almost all donors. The most frequent source of infection was nosocomial (50%). During the 5 years of the study, the number of candidates for autologous transfusion increased: 717 in 1992 to 1 528 in 1996. The prevalence of anti-hepatitis C virus in this older population (mean age: 64 years) decreased progressively (2.9% in 1992 to 1.1% in 1996, P<0, 01) since the prevalence of anti-HBc remained stable, near 12%. Among the 96 subjects found to be anti-hepatitis C virus positive before an autologous transfusion, 49 were transfused before 1990 and 40 had a history of surgery.

Conclusion: The prevalence of anti-hepatitis C virus has decreased since 1992 in blood donors and in candidates for autologous transfusion which may suggest that there is better screening in the general population and presenting the spread of hepatitis C virus infection.