Cross-sectional study of hepatitis B immunity in MSM between 2002 and 2012

Objectives Incidence of hepatitis B has not been well studied recently in men who have sex with men (MSM) despite increases in sexual risk practices and other sexually transmitted infections. Our aim was to determine the incidence of hepatitis B infection among MSM and level of immunity to hepatitis B attending a sexual health service over 10 years. Methods A cross-sectional analysis of all MSM attending Melbourne Sexual Health Centre (MSHC) from 1 July 2002 and 30 June 2012, and a retrospective cohort study of MSM who had attended MSHC on multiple occasions who had hepatitis serology done more than once. Results Of 10 031 MSM attending the clinic, 58.4% (95% CI 57.4% to 59.4%) (5655/9677) had hepatitis B surface antibody (HepBsAb), 10.6% (95% CI 10.0% to 11.4%) (840/7888) had core antibody (HepBcAb), and 3.7% (95% CI 3.0% to 4.5%) (95/2577) had surface antigen (HepBsAg). The proportion with HepBsAb decreased from 72% to 48% (p (trend)