Hepatitis C is caused by a virus and it's transmitted from blood contact....meaning if somehow, infected blood
got into his blood
. Risk factors include blood
transfusions, IV drug use, tattoos, body piercings, etc.
Hepatitis C (as well as alcohol use) can cause cirrhosis. The fact that he stopped drinking probably helped his liver, but cirrhosis doesn't really go away by itself. Successful treatment for Hepatitis C sometimes reverses some of the damage.