How is viral hepatitis diagnosed?

Blood tests. Viral hepatitis is inflammation of the liver caused by either hepatitis b, hepatitis a, or hepatitis c. Viral hepatitis can be prevented by vaccination for hepatitis a and b, but there is no vaccination for hepatitis c. The symptoms are often vague, such as fatigue, nausea and vomiting and diagnosed by abnormal liver function tests and by detection of the virus or antibodies to the virus in blood.