"No laboratory distinction can be made between acute and chronic (past or present) HCV infection. Diagnosis of chronic infection is made on the basis of anti-HCV positive results upon repeat testing. Approximately 75%-85% of newly infected persons develop chronic infection (14).

"Because of the high burden of chronic HCV infection in the United States and because no vaccine is available for preventing infection, national recommendations (15) emphasize other primary prevention activities, including screening and testing blood donors, inactivating HCV in plasma-derived products, testing persons at risk for HCV infection and providing them with risk-reduction counseling, and consistently implementing and practicing infection control in health-care settings."

Source

"Viral Hepatitis Surveillance - United States, 2010" (Atlanta, GA: US Centers for Disease Control Division of Viral Hepatitis), August 2012.