Enhanced Surveillance of Acute Hepatitis B and C in Four Health Regions in Canada, 1998 TO 1999

Abstract

OBJECTIVE:To assess the incidence and risk factors for acute hepatitis B and acute hepatitis C in a defined Canadian population. PATIENTS AND METHODS: An enhanced surveillance system was established in October 1998 to identify cases of acute hepatitis B and C infections in four regions in Canada, with a total population of approximately 3.2 million people. Information on demographic and clinical characteristics, laboratory results and potential risk factors was collected using predefined questionnaires. RESULTS: A total of 79 cases of acute hepatitis B and 102 cases of acute hepatitis C were identified from October 1998 to December 1999, resulting in an incidence rate of 2.3 and 2.9/100,000 person-years, respectively. Males had higher incidence rates than females. The incidence of acute hepatitis B peaked at age 30 to 39 years for both males and females, whereas acute hepatitis C peaked at 30 to 39 years for males and 15 to 29 years for females. At least 34% of acute hepatitis B and 63% of acute hepatitis C were associated with injection drug use. Persons who were 15 to 39 years of age were more likely to report injection drug use as a risk factor. Heterosexual contact was reported to be a risk factor for 36.6% of acute hepatitis B cases and 3.5% of acute hepatitis C cases. CONCLUSIONS: The surveillance provides national incidence estimates of clinically recognized acute hepatitis B and C. Both hepatitis B and C are important public health threats to Canadians. Prevention efforts for both diseases should focus on injection drug use, especially for people aged 15 to 39 years. Risky sexual behaviour is also a major concern in prevention of hepatitis B in Canada.

Serological and molecular epidemiological outcomes after two decades of universal infant hepatitis B virus (HBV) vaccination in Nunavut, Canada

“…Incidence for acute hepatitis B is estimated to be 2.3/100,000, with a higher incidence in men (3.0/100,000) compared to women (1.5/100,000) [67]. A large portion of cases occur within the immigrant population of Canada, as well as the Inuit and First Nations populations [68][69].…”

Epidemiology of Hepatitis B in Canada

“…The surveillance methods and operating procedures have been described in detail elsewhere (9). Briefly, a consensus protocol, and standardized case definitions and questionnaires were developed, and were used by all six health units.…”

“…Injection drug use and high risk heterosexual activities are the major risk factors associated with HBV transmission in Canada (9,16,28). Increasing years of sexual activity, multiple sexual partners and sex with HBeAg-positive carriers were associated with an elevated risk (29).…”

“…Increasing years of sexual activity, multiple sexual partners and sex with HBeAg-positive carriers were associated with an elevated risk (29). Homosexual activities, tattooing and body piercing, having an HBsAg car- Canada, 1998Canada, to 1999 rier in the family, and a history of blood transfusion also increase the risk of HBV infection among Canadians (9,29,30).…”

More Should Be Done to Protect Surgical Patients From Intraoperative Hepatitis B Infection

“…According to Zou et al 11 and unpublished data from Health Canada, 5 (11%) of 45 patients with acute hepatitis B in 1999 reported a history of hospitalization; 2 (6.7%) of them had no other risk factors. In 2000, 6 (9.8%) of 61 patients with acute hepatitis B reported a history of hospitalization and 3 (6.3%) reported hospitalization as the exclusive risk factor.…”