A population-based hepatitis B seroprevalence and risk factor study in a northern Ontario town

Objective: To determine: a) population based hepatitis B seroprevalence rates; and b) associated behavioural risk factors. Setting: A remote northern Ontario town with a cluster of hepatitis B cases. Interventions: Anonymous blood testing linked with risk-factor questionnaires. Results: 635 persons aged 14 to 30 years (51% of the eligible age cohort) donated blood in return for free vaccination; four were anti-HBs positive, and none was HBsAg positive. In all, 19% of participants reported two or more sexual partners in the previous year, 6% reported at least one tattooing in the previous year, and 1% reported illicit injection drug use. Of persons with multiple sexual partners 84% did not consistently use condoms. Conclusions: When the serological results of the original cluster (and contacts) were considered, the age cohort's HBsAg seroprevalence rate was estimated to be between 0.24% and 0.47%. While the serosurvey did not discover additional HBsAg positive cases, thee was great potential for heterosexual transmission.