[Hepatitis: associated diseases. Risk groups -- prevention -- treatment]

Area of Science:

• Hepatology and Virology
• Infectious Diseases
• Vaccinology

Context:

• Hepatitis B virus (HBV) infection is preventable through active vaccination, achieving high protection rates.
• Chronic HBV infection treatment with interferon and Lamivudine has limited efficacy (approx. 40%) and high relapse rates, with Lamivudine potentially inducing YMDD mutants.
• Hepatitis C virus (HCV) infection frequently progresses to chronicity (over 2/3 of cases) and vaccine development is hindered by viral variability.

Purpose:

• To review the current landscape of HBV and HCV infections, focusing on vaccination, treatment efficacy, and emerging therapeutic strategies.
• To highlight the challenges in managing chronic viral hepatitis, including treatment resistance and viral mutations.
• To compare the effectiveness of vaccination and treatment for HBV versus HCV.

Summary:

• Active HBV vaccination is highly effective. Chronic HBV treatment with interferon and Lamivudine shows moderate success but is complicated by relapse and YMDD mutations; Adefovir demonstrates promise with rapid HBV-DNA decline and improved liver histology without apparent mutant induction.
• Chronic Hepatitis C (HCV) infection develops in a majority of cases and is difficult to treat, with current combination therapies (pegylated interferons + Ribavirin) achieving sustained response in about 50% of patients.
• Treatment of non-responders and relapsers in chronic HCV remains a significant clinical challenge, underscoring the need for improved therapeutic options.

Impact:

• Highlights the critical role of active vaccination in preventing HBV infection.
• Identifies limitations of current chronic HBV treatments and introduces Adefovir as a potentially superior alternative.
• Underscores the persistent difficulties in treating chronic HCV, particularly for non-responders and relapsers.