HIV’s effect on Hepatitis C: Studies have shown that HIV infection in a person who is also infected with HCV results in higher levels of HCV in the blood, more rapid progression to HCV-related liver disease, and increased risk for cirrhosis and liver cancer. As a result, HCV is now regarded as an opportunistic infection in people with HIV infection, although it is not considered an AIDS-defining illness.

HCV’s effect on HIV: Some research suggests that infection with genotype 1 HCV is associated with more rapid progression to AIDS or death, although this is still controversial. Most people with HCV infection in the U.S. have genotype 1. Genotypes 2 and 3 are more common in Europe. Some evidence also indicates that HCV is associated with impaired CD4+ T cell recovery during antiretroviral therapy.