The prevalence of antibody to delta virus in western Canada.

To assess the prevalence and pathological role of hepatitis D virus (HDV) infection in western Canada, we tested a total of 310 sera from the province of Alberta, Yukon and Northwest Territories for antibody to HD (anti-HDV) by commercial solid phase radioimmunoassay. Two hundred and forty-five sera were hepatitis B surface antigen (HBsAg) positive. These were classified on the basis of clinical and biochemical data as either acute hepatitis, chronic hepatitis or in the healthy carrier phase of infection Sixty-five HBsAg negative sera from patients with other forms of chronic liver diseases served as controls. Anti-HDV was detected in only four of the HBsAg positive sera (1.6%) and in none of the controls. The prevalence of anti-HDV was significantly higher in patients with chronic hepatitis, three of twenty-two (13.6%) than in patients with acute hepatitis (0%) (p less than 0.05) or healthy carriers (0%) (p less than 0.005). Two of the four anti-HDV positive sera were obtained from patients with a history of parenteral drug abuse. These results indicate that HDV infection is uncommon in western Canada but, when it does occur, is more likely to be associated with chronic inflammatory liver disease. Parenteral drug abuse appears to be the major risk factor for HDV infection in western Canada at this time.