Viral clearance occurs very early during the natural resolution of hepatitis C virus infection in persons with haemophilia.

We studied spontaneous hepatitis C virus (HCV) RNA clearance in 12 haemophilic patients. In their earliest anti-HCV positive samples, HCV RNA was undetectable in eight patients (66%), positive by polymerase chain reaction (PCR) but negative by branched-DNA (bDNA) in three others, and quantifiable by bDNA (4839 IU/mL) in only one patient. In contrast, in earliest anti-HCV positive samples from eight matched controls who had persistent viremia, HCV RNA was quantifiable by bDNA in seven (P = 0.0008) and at higher levels (range 4644-678 515 IU/mL; median 43 532 IU/mL). From initial HCV infection, HCV RNA cleared in 7 months or less in four patients and in 1-2 years in six others. HCV persisted for 5 years before clearance in the absence of repeated exposure in one patient. We conclude that HCV clearance usually but not always occurs within 1-2 years after infection and is more likely in those with lower than in those with higher early viral loads.