The study is designed to evaluate interferon responses to CMV in HIV positive individuals and a component will look at interferon responses to CMV in HIV positive individuals over time after commencement of antiretroviral therapy. We will also look at the correlation between CD4 T cell numbers and HLA type with the interferon response.

Inclusion Criteria:

1. HIV positive with history of documented HCV infection
2. Over 18 years old
3. HIV positive
4. Antiretroviral naive, starting on antiretroviral therapy

HIV infected patients with past CMV infection initiating antiretroviral therapy