Viral hepatitis among young men who have sex with men: Prevalence of infection, risk behaviors, and vaccination

Background: Men who have sex with men (MSM) are at risk for acquiring hepatitis A virus (HAV), hepatitis B virus (HBV), and hepatitis C virus (HCV). Goal. The goal was to describe the seroprevalence of and risk factors for viral hepatitis, the frequency of vaccination against HAV and HBV, and reasons for lack of vaccination among young MSM. Study Design: We performed hepatitis serologies on 833 MSM aged 15 to 29 years who attended public venues in King County, Washington. Results: While 14.6% were HAV-immune due to vaccination, 13.9% had prior HAV infection; 57.9% were susceptible and 13.5% had unclear status. While 24.5% were HBV-immune due to vaccination, 13.3% had prior HBV infection; 44.2% were susceptible and 18.0% had unclear status. Prior HBV infection was associated with prior HAV infection. Men unvaccinated against HAV or HBV were unaware of the vaccines or had never been offered vaccination or perceived themselves at low risk for infection. Among 10 HCV-sero-positive men, 70.0% reported injection drug use. Conclusion: MSM must be vaccinated at an early age to prevent acquisition of HAV and HBV. Given the frequency of coinfection with HAV and HBV, a combined vaccine would be useful in this population.