The cascade of care for hepatitis C in Victoria, Australia: a data linkage cohort study.

BACKGROUND: Highly effective hepatitis C therapies are available in Australia. However, people living with hepatitis C face various barriers to accessing care and treatment. AIMS: To identify gaps in the cascade of care for hepatitis C and generate estimates of the number living with untreated infection according to population group, using a representative longitudinal study population. METHODS: We linked hepatitis C notification data from Victoria to national pathology, prescribing and death registry data. We assessed receipt of key clinical services in a large cohort who tested positive for hepatitis C from 1 January 2000 to 31 December 2016, with follow-up to 30 June 2018. We estimated the number still living with hepatitis C, adjusting for spontaneous clearance and mortality. RESULTS: The cohort comprised 45 391 people positive for hepatitis C. Of these, 13 346 (29%) received treatment and an estimated 28% (95% confidence interval (CI): 26-30%) were still living with chronic infection at 30 June 2018, with the remainder still living following spontaneous clearance (30%, 95% CI: 29-32%) or having died (12%, 95% CI: 12-12%). Half (50%) of those still living with hepatitis C were born from 1965 to 1980, and 74% first tested positive before 2011. CONCLUSIONS: Despite an enabling policy environment and subsidised therapy, many people in this cohort were not treated. Increased measures may be needed to engage people in care, including those who acquired hepatitis C more than 10 years ago.

The associations between invasive group A streptococcal disease and infection with influenza, varicella, or hepatitis C viruses: A data linkage study, Victoria, Australia.

OBJECTIVES: To quantify the associations between invasive group A streptococcal disease (iGAS) incidence and influenza, varicella, and chronic hepatitis C virus (HCV). METHODS: We used individual-level linked data of iGAS cases from Victoria, Australia (2007-2017) to assess associations between these viral infections and iGAS. A self-controlled case series method was used to estimate the relative incidence of iGAS following an influenza or varicella infection, while the relative incidence of iGAS among HCV cases, and HCV cases who inject drugs, was estimated using population-level data and a negative binomial regression model. RESULTS: Of the 1949 individuals with at least one iGAS diagnosis, 82 were diagnosed with influenza at least once, 30 with varicella, and 118 with HCV during the study period. The relative incidence of iGAS increased substantially following infection with influenza (incidence rate ratio [IRR]: 34.5, 95% confidence interval [CI]: 21.3-55.8) or varicella (IRR: 22.4, 95% CI: 10.3-48.8). iGAS incidence was higher among HCV cases (IRR: 5.7, 95% CI: 4.4-7.3) compared to individuals without HCV. iGAS incidence was also higher among HCV cases who inject drugs (IRR: 17.9, 95% CI: 13.0-24.4) compared to individuals without HCV who did not inject drugs. CONCLUSIONS: We found a significantly higher risk of iGAS following an influenza or varicella infection and for chronic HCV cases, particularly those who inject drugs. These findings are relevant to public health practice and support the timely identification of iGAS cases.

Missed opportunities for diagnosis of hepatitis B and C in individuals diagnosed with decompensated cirrhosis or hepatocellular carcinoma.

BACKGROUND AND AIM: This study aimed to assess utilization of health-care services in people with decompensated cirrhosis (DC) or hepatocellular carcinoma (HCC) and a "late diagnosis" of hepatitis B or hepatitis C. METHODS: Hepatitis B and C cases during 1997-2016 in Victoria, Australia, were linked with hospitalizations, deaths, liver cancer diagnoses, and medical services. A late diagnosis was defined as hepatitis B or hepatitis C notification occurring after, at the same time, or within 2 years preceding an HCC/DC diagnosis. Services provided during the 10-year period before HCC/DC diagnosis were assessed, including general practitioner (GP) or specialist visits, emergency department presentations, hospital admissions, and blood tests. RESULTS: Of the 25 766 notified cases of hepatitis B, 751 (2.9%) were diagnosed with HCC/DC, and hepatitis B was diagnosed late in 385 (51.3%). Of 44 317 cases of hepatitis C, 2576 (5.8%) were diagnosed with HCC/DC, and hepatitis C was diagnosed late in 857 (33.3%). Although late diagnosis dropped over time, missed opportunities for timely diagnosis were observed. Most people diagnosed late had visited a GP (97.4% for hepatitis B, 98.9% for hepatitis C) or had a blood test (90.9% for hepatitis B, 88.6% for hepatitis C) during the 10 years before HCC/DC diagnosis. The median number of GP visits was 24 and 32, and blood tests 7 and 8, for hepatitis B and C, respectively. CONCLUSIONS: Late diagnosis of viral hepatitis remains a concern, with the majority having frequent health-care service provision in the preceding period, indicating missed opportunities for diagnosis.

Modelling jurisdictional disparities in the cascade of care for chronic hepatitis B in Australia: impact of treatment uptake on mortality.

OBJECTIVE: Investigate the cascade of care for chronic hepatitis B (CHB) and estimate impacts of increasing treatment uptake on attributable burden, according to jurisdiction. METHODS: A mathematical model of CHB in Australia was utilised, combined with notifiable disease and Medicare data. We estimated the proportion with CHB who were diagnosed, engaged in care and receiving treatment in each state/territory, and projected future mortality. RESULTS: The highest uptake of all measures was in New South Wales, however, the largest increase over time occurred in Northern Territory. No jurisdiction is due to meet 2022 targets of treatment uptake or mortality reduction. Previously declining mortality is predicted to plateau or increase in all jurisdictions except Northern Territory. The largest gap in the cascade of care was most commonly diagnosed individuals not engaged in care; however, in Victoria and Tasmania it was lack of diagnosis. CONCLUSIONS: Measures of the cascade of care varied substantially between jurisdictions; while all require improvements to reduce mortality, the specific gaps vary, as do potential impacts. IMPLICATIONS FOR PUBLIC HEALTH: Improving the cascade of care for CHB will require jurisdictionally tailored approaches. If improvements are not made, more deaths will occur due to CHB in most states and territories.

The Inaugural Australian Centre for Hepatitis Virology Public Panel Discussion on Viral Hepatitis Research-Lessons in Scientific Community Outreach.

Viral hepatitis remains one of the most significant health issues globally, directly responsible for over 1 million deaths each year and affecting almost 300 million people around the world. Scientific research in recent decades has brought about improvements in the lives of people living with chronic viral hepatitis. On the 29 July 2021, the Australian Centre for Hepatitis Virology (ACHV) for the first time held a public educational forum for the general public. The main aim of this event was to inform the affected community about the importance of scientific research and give an overview of upcoming developments in the field. Here, we provide a detailed report of the panel discussion (including its organisation, execution, and lessons learned to incorporate into future events) and provide strategies that can be used by other scientific societies to hold similar events in their own communities.

Adherence in chronic hepatitis B: associations between medication possession ratio and adverse viral outcomes.

BACKGROUND: Antiviral therapy for chronic hepatitis B (CHB) is effective and can substantially reduce the risk of progressive liver disease and hepatocellular carcinoma but is often administered for an indefinite duration. Adherence has been shown in clinical trials to maximize the benefit of therapy and prevent the development of resistance, however the optimal threshold for predicting clinical outcomes has not been identified. The aim of this study was to analyse adherence using the medication possession ration (MPR) and its relation to virological outcomes in a large multi-centre hospital outpatient population, and guide development of an evidence-based threshold for optimal adherence. METHODS: Pharmacy and pathology records of patients dispensed CHB antiviral therapy from 4 major hospitals in Melbourne between 2010 and 2013 were extracted and analysed to determine their MPR and identify instances of unfavourable viral outcomes. Viral outcomes were classified categorically, with unfavourable outcomes including HBV DNA remaining detectable after 2 years treatment or experiencing viral breakthrough. The association between MPR and unfavourable outcomes was assessed according to various thresholds using ROC analysis and time-to-event regression. RESULTS: Six hundred forty-two individuals were included in the analysis. Median age was 46.6 years, 68% were male, 77% were born in Asia, and the median time on treatment was 27.5 months. The majority had favourable viral outcomes (91.06%), with most having undetectable HBV DNA at the end of the study period. The most common unfavourable outcome was a rise of < 1 log in HBV DNA (6.54% of the total), while 2.49% of participants experienced viral breakthrough. Adherence was linearly associated with favourable outcomes, with increasing risk of virological breakthrough as MPR fell. Decreasing the value of MPR, at which a cut-point was taken, was associated with a progressively larger reduction in the rate of unfavourable event; from a 60% reduction under a cut-point of 1.00 to a 79% reduction when the MPR cut-point was set at 0.8. CONCLUSION: Lower adherence as measured using the MPR was strongly associated with unfavourable therapeutic outcomes, including virological failure. Optimising adherence is therefore important for preventing viral rebound and potential complications such as antiviral resistance. The evidence of dose-response highlights the need for nuanced interventions.

Epidemiology of chronic hepatitis B and C in Victoria, Australia: insights and impacts from enhanced surveillance.

OBJECTIVE: To assess the impact of an enhanced viral hepatitis surveillance program on data completeness and on epidemiological assessment of affected populations. METHODS: Notified cases of non-acute hepatitis B and C were analysed to determine demographic characteristics and risk factors during the period prior to July 2015-June 2016, and during enhanced surveillance of the period July 2016-June 2017, during which time doctors were contacted for information about new diagnoses. RESULTS: During the enhanced period, completeness for country of birth and Indigenous status doubled for both hepatitis B and hepatitis C, from 18-37% to 48-65%. The incidence ratio of hepatitis C among Aboriginal and Torres Strait Islander people increased from eight-fold to 11.4-fold, and the proportion of hepatitis B cases reported as born in China and Vietnam relative to other countries increased. New data fields identified that 12% of hepatitis C diagnoses occurred in a correctional facility, and 2% of hepatitis B cases were healthcare workers. CONCLUSIONS: Improved data completeness highlighted the underlying epidemiology of chronic viral hepatitis, demonstrating the increased burden of infection among specific priority populations. Implications for public health: Enhanced surveillance provides greater insight into the epidemiology of chronic viral hepatitis, identifying groups at risk and opportunities for public health action.

Chronic hepatitis B prevalence in Australian Aboriginal and Torres Strait Islander people before and after implementing a universal vaccination program: a systematic review and meta-analysis.

Background A higher prevalence of chronic hepatitis B (CHB) has been reported in Aboriginal and Torres Strait Islander (Aboriginal) compared with non-Aboriginal Australians. An Australian infant and adolescent hepatitis B virus (HBV) vaccination program was implemented in 2000. Meta-analysis methods will be used to examine if the pooled prevalence of CHB decreased after 2000 among Aboriginal Australians. METHODS: Embase, Medline and Web of Science were searched from 1 January 1981 to 29 March 2018 and all issues of the Northern Territory and New South Wales Public Health Bulletins. Studies needed to report the number of individuals who were tested and tested positive for hepatitis B surface antigen (HBsAg). RESULTS: There were 36 studies; 16 before and 20 after 2000; reporting 84 prevalence estimates. Population groups included: adults (14 studies), pregnant women (13 studies), prisoners (five studies) children or teenagers (10 studies) and infants (two studies). The pooled prevalence of HBsAg decreased overall (from 10.8% before 2000 vs 3.5% after 2000), in women (4.2% vs 2.2%), in males (17.5% vs 3.5%), in regional (7.8% vs 3.9%) and remote (14.4% vs 5.7%) areas, in New South Wales (12.3% vs 3.0%), in the Northern Territory (6.1% vs 5.1%), in adults (15.3% vs 4.3%) and in pregnant women (3.6% vs 2.6%). CONCLUSION: The prevalence of HBsAg decreased among Aboriginal people after 2000.

Bridging the access gap: Medicare ineligibility in people living with chronic hepatitis B.

People living in Australia on temporary student or work visas are excluded from Medicare access and can face barriers to adequate healthcare, even if they are privately insured. This analysis aimed to quantify this issue in relation to people living with chronic hepatitis B, the majority of whom in Australia were born overseas. The data suggest that an estimated 25 000 people living with chronic hepatitis B in Australia are ineligible for Medicare, 10% of the total number affected, with considerable potential impact in access to effective healthcare and prevention of adverse outcomes.

Cultural and linguistic diversity of people living with chronic hepatitis B in 2011-2016: changing migration, shifting epidemiology.

OBJECTIVE: To estimate the cultural and linguistic diversity in Australians currently living with chronic hepatitis B (CHB), the majority of whom were born overseas, and to identify trends in this diversity over time. METHODS: Estimates were generated by combining Australian census country of birth information with seroprevalence data generated from antenatal serology linked with surveillance notifications. The number of people living with CHB was assessed according to country of birth using the 2011 and 2016 censuses. RESULTS: The total number of Australian residents living with CHB increased by 20% between 2011 and 2016, substantially outpacing population growth. The most common country of birth continued to be China, with the number of Chinese-born Australians living with CHB increasing by 60% in the 5-year period. Decreased numbers were observed for people born in European countries. CONCLUSIONS: The epidemiology of chronic hepatitis B in Australia has shifted over time due to changing migration patterns, with increases in many countries in the Asia-Pacific, African and Middle Eastern regions. Implications for public health: Interventions to improve the health of people living with CHB are imperative, and these up-to-date estimates identify priority groups and communities, which are constantly changing.

Hepatocellular carcinoma over three decades in Victoria, Australia: epidemiology, diagnosis and trends, 1984-2013.

BACKGROUND: Liver cancer continues to be a health priority in Australia, with the majority attributable to preventable causes, and certain populations at higher risk. AIMS: Epidemiological assessment of incidence, trends and distribution to inform prevention, and reassessment of data in light of recent changes to registry case definitions. METHODS: Reported cases of hepatocellular carcinoma (HCC) in Victoria, Australia, 1984-2013, were obtained from the Victorian Cancer Registry. Demographic characteristics were examined, incidence and survival assessed using Poisson and Cox regression, and geographic distribution mapped. Incidence was compared before and after inclusion of non-histologically confirmed cases in Registry data to assess impacts on incidence trends. RESULTS: Diagnoses of HCC rose substantially between 1984 and 2013, increasing sixfold from 0.9 to 5.9 per 100 000. The rate of increase per year accelerated from 5.3% between 1984 and 2003 to 9.5% between 2004 and 2013. Cases were disproportionately male (80%), median age at diagnosis was 66 years and 53% were born overseas. Even during 2004-2013, 5-year survival was only 16%, although higher among younger people, metropolitan residents and people born overseas. Incidence showed strong geographic clustering. The proportion of cases diagnosed clinically increased from 1% during 1984-2004 to 43% in 2009-2013. The revised case definition added 993 cases (27.3% of total). CONCLUSION: Cases of HCC are becoming increasingly common, and revised incidence estimates highlight the impact of case definitions in the context of changing diagnostic approaches. The ongoing burden, disproportionate population distribution and low survival emphasise the importance of prevention and early detection as a public health imperative.

Limited provision of diagnostic services to Victorians living with hepatitis C antibodies, 2001-2012: a multi-level modelling analysis.

OBJECTIVE: To determine what percentage of Victorians with a history of notified hepatitis C exposure received appropriate follow-up diagnostic services between 2001 and 2012. METHODS: Individual notification data and aggregate Medicare and supplementary testing data were entered into a compartmental transition model, which was used to estimate the percentage of people with a hepatitis C notification who were yet to receive either a negative diagnostic test for viral nucleic acid, or a test for viral genotype, at the end of 2012. RESULTS: We estimate that 58.2% (uncertainty interval: 42.2%, 72.4%) of Victorians with a hepatitis C notification between 2001 and 2012 did not receive either a negative test for viral nucleic acid or a viral genotyping test during the study period. At the end of 2012, we estimate there were approximately 20,400 Victorians living with hepatitis C antibodies who were yet to receive testing, of which approximately 9,300 would have been aged 45 years or older. CONCLUSIONS: A majority of people living with HCV antibodies in Victoria had not received appropriate secondary diagnostic services as of the end of 2012. IMPLICATIONS: As improved therapeutic options become available for people living with chronic hepatitis C, measures to support appropriate follow-up of people with suspected or confirmed chronic infections via primary care services will be required.

Uptake and trends in ordering of funded hepatitis B immunisation for priority populations in Victoria, Australia, 2013-2014.

Background The Department of Health and Human Services in Victoria provides funded hepatitis B vaccine to many priority groups at risk of acquiring infection. We aimed to determine the uptake of vaccine ordering for at-risk groups over time, to assess any trends and identify any gaps in prevention of hepatitis B for those at risk. METHODS: Routinely collected administrative data regarding the indication for vaccine ordered by practitioners were analysed for the period June 2013 to December 2014. Number of doses and courses distributed was determined and compared with the estimated size of the priority populations. RESULTS: During the 18-month period assessed, 20498 doses of funded hepatitis B vaccine were ordered, equating to ~5700 complete courses, with the overall number of orders per quarter increasing between 2013 and 2014. The most common indication was being a household or sexual contact of people living with hepatitis B (2803 courses, 49.2% of the total), equating to approximately one course per new chronic hepatitis B notification. The remaining doses were largely distributed to people living with HIV (648 courses, 11.4%), people living with hepatitis C (621 courses, 10.9%), and people who inject drugs (594 courses, 10.4%). CONCLUSIONS: This analysis demonstrates that access to hepatitis B immunisation among priority populations appears to have increased in Victoria during 2013-14, however it could still be improved. Continued assessment of these data over time will be important to measure the impact of interventions on increasing the reach of the funded vaccine program.

Hepatitis B virus epidemiology.

The epidemiology of hepatitis B virus (HBV) infection is geographically diverse, with population prevalence, age and mode of acquisition, and likelihood of progression to chronic infection mutually interdependent. The burden of chronic HBV infection is increasingly being recognized, with cirrhosis and liver cancer attributable to HBV continuing to increase. The outcomes of chronic HBV infection are affected by a range of factors, including viral genotype, the presence of coinfections with other blood-borne viruses, and the impact of other causes of liver disease. The increased recognition of HBV infection as a leading cause of death globally has resulted in the development of new structures and policies at the international level; immediate attention to implementing these strategies is now required.