[A comparative study of primary and re-infection with hepatitis C]

A nested polymerase chain reaction (PCR) was used to assess HCV re-infection and primary infection. In 10 hepatitis cases defined as primary infection, 9 showed clinical hepatitis, and 1 case was subclinical; the interval between transfusion and elevation of alanine aminotransferase (ALT) levels was 15-60 (37.9 + 13.9) days. 10/10 and 7/10 were persistently positive for anti-HCV and HCV RNA for more than 1 year respectively. Similarly, in 5 cases defined as re-infection, 4/5 showed clinical hepatitis, the interval between transfusion and elevation of ALT was 30-46 (34.8 +/- 6.4) days, and 5/5 and 3/5 were persistently positive for anti-HCV and HCV RNA for more than 1 year respectively. All 5 re-infected recipients showed abnormal ALT. In conclusion, there was no significant difference (P > 0.05) in the aspect of the clinical figure, ALT abnormality, the duration of anti-HCV and HCV RNA etc. Resulting from primary or re-infection with HCV, suggesting that primary infection fail to induce a Protective immune response.