Chronic Hepatitis B in Canada

Abstract

Recent developments in the treatment and prevention of hepatitis B virus (HBV) infections warrant revisiting important epidemiological questions, such as how prevalent is chronic HBV infection in Canada, in which Canadian subpopulations are HBV prevalence rates the highest, in what percentage of infected individuals is the virus actively replicating, and how many infected Canadians are candidates for antiviral therapy? Currently available data suggest the overall prevalence of HBVinfected individuals in the general population is approximately 2%, with 5% to 10% having serological evidence of previous HBV infection. In high risk groups, such as street-connected individuals, Aboriginals and immigrants from endemic areas, these rates of viral prevalence and serological evidence of previous HBV infection are approximately two to 10 and five to 10 times higher, respectively, than in the general population. Candidates for antiviral therapy range from less than 1% of infected Aboriginals to 15% to 30% of Asians with chronic HBV. From these data, it is clear that chronic HBV remains an important public health problem in this country. Hence, resources must be identified to enhance Canadians' awareness of HBV infection, maintain, if not expand, efforts to identify and implement safe and effective antiviral therapy for HBV-infected individuals, and continue programs for universal vaccination to prevent new HBV infections.Key Words: Canada; Epidemiology; Hepatitis; Hepatitis B; Hepatitis B virus; Liver; Liver disease L'hépatite B chronique au Canada RÉSUMÉ : Compte tenu de récents progrès réalisés aux chapitres du traitement et de la prévention de l'hépatite B, il semble justifié de revoir les grandes questions épidémiologiques, par exemple, quelle est la prévalence de l'hépatite B chronique au Canada, dans quelle sous-population du Canada les taux de prévalence du HBV sont-ils les plus élevés, dans quel pourcentage des sujets infectés le virus se multiplie-t-il activement et combien de Canadiens infectés sont des candidats au traitement antiviral? Selon les données actuellement disponibles, la prévalence globale de l'infection au HBV dans la population générale s'élèverait à environ 2 %, de 5 à 10 % présentant des signes sérologiques d'infection au HBV. Dans les groupes à risque, par exemple chez les sans-abris, les Autochtones et certaines populations immigrantes provenant de régions endémiques du globe, ces taux de prévalence globale et de signes sérologiques d'infection au HBV sont de 2 à 10 et de 5 à 10 fois plus élevés respectivement que dans la population en général. Les pourcentages de candidats au traitement antiviral varient de moins de 1 % chez les Autochtones infectés à 15 ou 30 % chez les Asiatiques porteurs d'une infection chronique par le HBV. À partir de ces données, il est clair que le HBV reste un important problème de santé publique dans ce pays. Des ressources doivent donc être trouvées pour sensibiliser davantage les Canadiens au HBV, pour maintenir sinon élargir les efforts déployés pour découvrir e...

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