Hepatitis B infection and vaccination coverage in men who have sex with men consulting a Danish venereal disease clinic

BACKGROUND: Vaccination guidelines from the Danish Health and Medicines Authority recommend vaccination of all men who have sex with men (MSM) against hepatitis B virus (HBV). The only existing data on HBV infection in Danish MSM stem from 1984: 58% of MSM attending venereal clinics in Copenhagen had a prior and 4% had a chronic HBV infection. The aim of this study was to provide up-to-date data on the prevalence of HBV infection and vaccination coverage among Danish MSM.

METHODS: At the venereal clinic at Aarhus University Hospital, 1525 consecutive patients received a questionnaire covering risk group and vaccination status; moreover, HBV serology was performed. Prevalence proportions of serological signs of vaccination, infection, etc. were stratified according to self-reported risk group and vaccination status.

RESULTS: In total, 141 patients were MSM. Among these, 14% (CI = 9-21%) were vaccinated, 7% (CI = 3-13%) had a prior infection and 1.4% (CI = 0.2-5%) were HBsAg positive. In patients recalling three doses of vaccination, 18% (CI = 11-26%) were anti-HBs negative and 0.8% (CI = 0.02-5%) were HBsAg positive. Similar data for other risk groups and the total clientele are presented.

CONCLUSIONS: This study presents the first Scandinavian data on the prevalence of HBV infection and vaccination among MSM since the introduction of the vaccine. Danish health authorities should evaluate whether a carrier frequency of 1.4% and a vaccination coverage of 14% in MSM is acceptable or warrants intensified focus on vaccination. Prospective vaccination campaigns should consider prevaccination testing, since 18% of patients recalling three doses of vaccination were anti-HBs negative.