Hepatitis B status in migrants and refugees: increasing health burden in Western Australia.

Background:  In light of increasing migration from endemic countries with chronic hepatitis B (CHB), this study describes the changing epidemiology of CHB patients born outside Australia referred to a tertiary hospital in Western Australia. It aims to stratify risk and progression to cirrhosis and hepatocellular carcinoma according to viral factors and to provide an indication of the growing burden of disease and current and future treatment costs. Methods:  Demographic, serological and biochemical data were obtained from patients with CHB between July 2002 and December 2008. Hepatitis B virus DNA quantification was performed to assess baseline viral loads in the patients. Total cost estimates for surveillance and treatment are based on probabilities of the population anticipated to be at a given stage of the disease in a given year. Results:  There is a progressive increase in referrals (n = 478) with the majority coming from Asia (57%) and Africa (35%). The mean age of Africans is 11 years less than that of Asians, with a lower proportion of Africans having hepatitis B virus DNA > 2000 IU/mL compared with Asians (36.7% vs 54.3%). Approximately 50% of CHB patients referred are at risk of cirrhosis and hepatocellular carcinoma unless treated. Without treatment, a substantial increase in cost over 10 years (from $401 460 to $2 027 078) is estimated at 400%. Conclusion:  This study highlights the increasing burden of CHB in Western Australia, from people born in endemic countries, in particular, the direct costs of treatment. It will help to develop strategies that can be tailored to Western Australia with appropriate allocation of resources.