Hepatitis C: epidemiology, natural history, and diagnosis

An estimated 71 million people have chronic hepatitis C virus (HCV) infection worldwide. Spontaneous clearance of HCV occurs in minority cases with 15%–25%, and chronic hepatitis C can cause cirrhosis, hepatocellular carcinoma, and extrahepatic manifestations over a 20–30 years period. Liver fibrosis generally progresses slowly but can be accelerated by host, viral, and environmental factors. Therefore, fibrosis status should be assessed by noninvasive methods regularly. The diagnosis of chronic HCV infection is based on the detection of both anti-HCV antibodies and HCV RNA. There are four main routes of HCV transmission: inject drug use, healthcare-associated transmission, mother-to-child transmission, and sexual transmission. Because of the absence of vaccine for HCV, prevention of HCV infection and reinfection is warranted to reduce the risk of HCV-related complications.