355 Ch 354. Viral Hepatitis — HAV, HBV, HCV, HDV, and HEV

Viral hepatitis 五大型：(1) HAV — RNA, fecal-oral, self-limited acute；(2) HBV — DNA, partially dsDNA, parenteral/sexual/perinatal, chronic in 5% adult / 90% perinatal；(3) HCV — RNA, parenteral, chronic in 75-85%，DAAs (direct-acting antivirals) cure > 95%；(4) HDV (delta) — requires HBV co-infection；(5) HEV — RNA, fecal-oral (water-borne in developing; pork/deer in developed), self-limited usually but severe in pregnancy + chronic in immunocompromised；台灣 HBV burden historically high (~ 15% pre-vaccine era)；vaccine + maternal antiviral has reduced；HBV management：treat if active disease (ALT 持續 ↑, fibrosis, cirrhosis) — entecavir or tenofovir (TDF/TAF)；HCV management：all chronic HCV should be treated with DAAs — sofosbuvir/velpatasvir, glecaprevir/pibrentasvir, sofosbuvir/ledipasvir, etc., 8-12 weeks, > 95% cure；HBV functional cure (HBsAg loss) emerging with siRNAs (bepirovirsen) + capsid inhibitors；HCC surveillance for chronic HBV + cirrhosis；vaccinations：HAV + HBV recommended。