Viral hepatitis

More than 5 million persons living in America are chronically infected with one form of viral hepatitis. In the United States, chronic hepatitis is the leading cause of chronic liver disease, liver cirrhosis, and liver cancer. Additionally, many more people will contract an acute form of viral hepatitis but fortunately will recover and clear the virus. 

There are different viruses that can cause hepatitis and these are fairly recent discoveries. Hepatitis A and hepatitis B viruses were first identified after the Second World War. In the early 1970s, a third form of hepatitis virus was identified that was neither hepatitis A nor hepatitis B. This new disease was called "non-A, non-B hepatitis," until 1989 when researchers sequenced the viral genome and the virus was named hepatitis C. 

Most recently, hepatitis D and E viruses have been identified, with hepatitis D being shown to require the helper function of the hepatitis B virus to replicate, and hepatitis E virus being the major etiologic agent of enterically transmitted non-A, non-B hepatitis worldwide. 

Also please visit the related section on Bloodborne Pathogens.