Hepatitis B immunization for indigenous adults, Australia.

Andre Louis Wattiaux,Benjamin Cowie,Steve Wesselingh,Kristine Macartney,Frank Beard,J Kevin Yin,James Ward

doi:10.2471/blt.16.169524

Abstract

ObjectiveTo quantify the disparity in incidence of hepatitis B between indigenous and non-indigenous people in Australia, and to estimate the potential impact of a hepatitis B immunization programme targeting non-immune indigenous adults.MethodsUsing national data on persons with newly acquired hepatitis B disease notified between 2005 and 2012, we estimated incident infection rates and rate ratios comparing indigenous and non-indigenous people, with adjustments for underreporting. The potential impact of a hepatitis B immunization programme targeting non-immune indigenous adults was projected using a Markov chain Monte Carlo simulation model.FindingsOf the 54 522 persons with hepatitis B disease notified between 1 January 2005 and 31 December 2012, 1953 infections were newly acquired. Acute hepatitis B infection notification rates were significantly higher for indigenous than non-indigenous Australians. The rates per 100 000 population for all ages were 3.6 (156/4 368 511) and 1.1 (1797/168 449 302) for indigenous and non-indigenous people respectively. The rate ratio of age-standardized notifications was 4.0 (95% confidence interval: 3.7–4.3). If 50% of non-immune indigenous adults (20% of all indigenous adults) were vaccinated over a 10-year programme a projected 527–549 new cases of acute hepatitis B would be prevented.ConclusionThere continues to be significant health inequity between indigenous and non-indigenous Australians in relation to vaccine-preventable hepatitis B disease. An immunization programme targeting indigenous Australian adults could have considerable impact in terms of cases of acute hepatitis B prevented, with a relatively low number needed to vaccinate to prevent each case.

Highlights

Australia in 2016 has a population of approximately 24 million people
confidence intervals (CI): confidence interval; NA: not applicable. a Indigenous population was individuals who self-identified in the Australian census as being Aboriginal or Torres Strait Islander or both; non-indigenous was the remaining resident Australian population
Consistent with a previous study,[23] we found that rates of notification for newly acquired hepatitis B were significantly higher for indigenous than non-indigenous Australians

Summary

Introduction

Australia in 2016 has a population of approximately 24 million people. Indigenous Australians (Aboriginal and Torres Strait Islander peoples) constitute 3.0% of the population and have a younger age structure than non-indigenous Australians, similar to that of low- and middle-income countries.[1]. Total viral hepatitis-related mortality in the Western Pacific Region of the World Health Organization (WHO) is higher than deaths due to acquired immune deficiency syndrome, malaria and tuberculosis combined, constituting a critical public health challenge for the Region.[5,6] In Australia, hepatitis B vaccination was recommended (but not nationally funded) for infants and adults in high-risk groups, including indigenous Australians, in the late 1980s.7. Universal vaccination of all infants commenced in the Northern Territory of Australia in 1990, followed by a funded national adolescent immunization programme starting in 1997. A funded universal infant hepatitis B immunization programme was introduced nationally in May 2000.7 The seroprevalence of hepatitis B virus surface antigen (HBsAg) in indigenous Australian adults was estimated to be

Methods

Results

Conclusion