Hepatitis C is a virus that can cause inflammation of the liver transmitted through contact with blood. Although the likelihood of sexual transmission is low this risk is increased if you have other STIs or are engaging in rough sex and/or fisting. Being infected with HIV can increase the likelihood of transmission and acquisition of hep C during sex. Diagnosis is by a blood test. Standard treatment for hep C is combination of 2 drugs. With treatment there is a 50 to 90 percent chance of clearing the virus.