eLife Assessment
The authors examined the evolution of hepatitis C virus (HCV) in a cohort of 14 subjects with recent HCV infections. By using computational methods, they showed that viral fitness declines as the virus mutates to escape the immune response and can rebound later in infection as HCV accumulates additional mutations. The study contributes to an important aspect of viral evolution. The combination of approaches is highly compelling; however, some aspects of the manuscript are incomplete and would greatly benefit from additional revision, mainly to increase their clarity.