Hepatitis C Support Group
Hepatitis C is a blood-borne viral disease which can cause liver inflammation, fibrosis, cirrhosis and liver cancer. The hepatitis C virus (HCV) is spread by blood-to-blood contact with an infected person's blood. Many people with HCV infection have no symptoms and are unaware of the need to seek treatment. Hepatitis C infects an estimated 150-200 million people worldwide.

AnikaHekla covered it well for the VL. part, can't add to that.
Specific enzymes, Alt/Ast, according to my Tx N.P. (Nurse) leak into the blood stream from a damaged liver. It is not possible to tell how bad the damage is by the numbers. For the most part, high numbers are not desirable but are mainly used as a baseline to watch for abnormal spikes. Huge jumps indicate only that SOMETHING is going on and needs to be looked at. Usually via biopsy (Bx)
After freaking so often back in the days of yore here, I now see my lab numbers and make no assumptions. All I do know is that I need to treat as soon as possible just because .... the bugs have been partying in there for 44 years and I'm tired of them - unwelcome guests.