A recent study utilized next-generation sequencing (NGS) to distinguish between hepatitis C virus (HCV) reinfection and relapse in six patients who achieved sustained virologic response (SVR) after direct-acting antiviral (DAA) treatment. NGS of the HCV NS5B gene was conducted before treatment (T0), after RNA rebound (T1), and after a second rebound for one patient (Pt3). Reinfection confirmed in Pt5 and Pt3’s first rebound. Viral relapse identified in Pt6 (between T0 and T1) and Pt3 (between T1 and T2). Low Z-scores (<2.58) in Pt1 and Pt2 indicated related viral quasispecies, suggesting relapse. Higher Z-score in Pt4 hinted at possible reinfection. The study highlights NGS’s effectiveness in differentiating HCV reinfection from relapse through genetic analysis over time, with Z-scores as a pivotal analytical tool.

Reference:  Minosse C, Gruber CEM, Rueca M, et al. Late Relapse and Reinfection in HCV Patients Treated with Direct-Acting Antiviral (DAA) Drugs. Viruses. 2021;13(6):1151. Published 2021 Jun 16. doi:10.3390/v13061151