In the majority of instances acute viral hepatitis resolves totally without sequelae. Fulminant hepatitis is a highly lethal lesion but 20 to 25 per cent of patients, principally young patients, survive. Survivors do not appear to develop chronic liver disease. Persistent viral hepatitis follows acute icteric hepatitis, both type B and non-B, in 10 to 12 per cent of patients. Six long-term HBs Ag carriers demonstrated HBs Ag clearance after 14-73 months. Chronic active viral hepatitis often progresses to cirrhosis. This progressive hepatitis appeared as a sequelae of acute icteric type B hepatitis in 3 per cent of 429 patients. In patients with chronic active type B hepatitis, low titers of HBs Ag are common.