Acute hepatitis C virus infection: clinical update and remaining challenges

Acute hepatitis C virus (HCV) infection is a global health concern with substantial geographical variation in the incidence rate. People who have received unsafe medical procedures, used injection drugs, and lived with human immunodeficiency virus are reported to be most susceptible to acute HCV infection. The diagnosis of acute HCV infection is particularly challenging in immunocompromised, reinfected, and superinfected patients due to difficulty in detecting anti-HCV antibody seroconversion and HCV ribonucleic acid from a previously negative antibody response. With an excellent treatment effect on chronic HCV infection, recently, clinical trials investigating the benefit of direct-acting antivirals (DAAs) treatment for acute HCV infection have been conducted. Based on the results of cost-effectiveness analysis, DAAs should be initiated early in acute HCV infection prior to spontaneous viral clearance. Compared to the standard 8-12 week-course of DAAs for chronic HCV infection, DAAs treatment duration may be shortened to 6-8 weeks in acute HCV infection without compromising the efficacy. Standard DAA regimens provide comparable efficacy in treating HCV-reinfected patients and DAA-naive ones. For cases contracting acute HCV infection from HCV-viremic liver transplant, a 12-week course of pangenotypic DAAs is suggested. While for cases contracting acute HCV infection from HCV-viremic non-liver solid organ transplants, a short course of prophylactic or pre-emptive DAAs is suggested. Currently, prophylactic HCV vaccines are unavailable. In addition to treatment scale-up for acute HCV infection, practice of universal precaution, harm reduction, safe sex, and vigilant surveillance after viral clearance remain critical in reducing HCV transmission. (Clin Mol Hepatol 2023;29:623-642)

Automated summary

Acute hepatitis C virus (HCV) infection, with varying incidence rates globally, is most common in individuals who have received unsafe medical procedures, used injection drugs, and lived with human immunodeficiency virus. Diagnosing acute HCV infection is challenging in immunocompromised, reinfected, and superinfected patients due to difficulties in detecting anti-HCV antibody seroconversion and HCV ribonucleic acid. Clinical trials have recently shown the treatment benefits of direct-acting antivirals (DAAs). Early initiation of DAAs is recommended for acute HCV infection before spontaneous viral clearance, and shorter treatment durations can be effective. Standard DAA regimens have similar efficacy in treating HCV-reinfected patients and DAA-naive ones. For specific cases, such as HCV-viremic liver and non-liver solid organ transplant recipients, different treatment durations and courses of DAAs are suggested. Prophylactic HCV vaccines are currently unavailable, so prevention measures, harm reduction, safe sex, and vigilant surveillance after viral clearance are crucial for reducing HCV transmission. (Clin Mol Hepatol 2023;29:623-642)