HIV-positive men who have sex with men (MSM) living in New York City who clear hepatitis C virus (HCV), whether spontaneously or with antiviral treatment, are reinfected with hep C at a high rate, most likely through sexual exposure.

Researchers analyzed data from 305 HIV-positive MSM participants in an ongoing New York City cohort study who cleared HCV and were followed for a median of 2.2 years.

Thirty-eight (12 percent) of the men were reinfected. This happened after a median of 1.9 years and up to 11 years after initial viral clearance. This translated to a reinfection rate of 4.4 cases per 100 cumulative years of follow-up—more than seven times greater than the rate of first-time HCV infections among HIV-positive MSM in New York City. Thirty-three of those men’s HCV was cleared, and six of them were reinfected again, for a second reinfection rate of 8.7 per 100 cumulative years.

Daniel S. Fierer, MD, an infectious disease specialist at the Icahn School of Medicine at Mt. Sinai in New York City and the study’s lead author, says many MSM in this cohort “might forget or not really believe that they were infected during sex. So ongoing counseling is important to reinforce the message.”