Country of birth and other factors associated with hepatitis B prevalence in a population with high levels of immigration

Targeted antiviral treatment of hepatitis B virus in culturally and linguistically diverse populations to achieve elimination targets in Australia

The majority of Australia's hepatitis B virus (HBV) burden is borne by culturally and linguistically diverse (CALD) populations, and antiviral treatment is the mainstay of intervention. Using modelling, we estimated the impact of targeted antiviral treatment scale-up and changes in migration on HBV-related mortality and HBV elimination in CALD populations in Australia. We fitted a deterministic mathematical model based on the natural history of HBV and the Australian migration effect in four CALD population groups according to country of birth. We used three antiviral treatment scale-up scenarios: baseline (9.3% coverage); intermediate (coverage of 80% of patients eligible for antiviral therapy by 2030); and optimistic (coverage of 20% of all patients living with HBV by 2022). Our model predicted that if the baseline treatment is followed between 2015 and 2030, the number of chronic HBV cases and HBV-related mortality will increase. Following the optimistic scale-up, the number of new HBV cases could be reduced by 78%, 73%, 74% and 83% in people born in Asia-Pacific, Europe, Africa and the Middle East, and Americas, respectively, between 2015 and 2030. An optimistic treatment scale-up could result in a 19.2%-24.5% reduction in HBV-related mortality and a 15%-25% reduction in HCC-related mortality in CALD populations between 2015 and 2030. In conclusion, our findings highlight that targeted antiviral treatment for CALD populations provides significant health system benefits by reducing HBV-related complications from cirrhosis and HCC. Expanded antiviral treatment programmes focusing on high-prevalence CALD populations may be an effective strategy to reduce HBV-related morbidity and mortality.

Fitting Health Care to People: Understanding and Adapting to the Epidemiology and Health Literacy of People Affected by Viral Hepatitis from Culturally and Linguistically Diverse Migrant Backgrounds

This study explored the epidemiology and health literacy of people affected by viral hepatitis (VH) from migrant culturally and linguistically diverse (CALD) backgrounds attending a community-based general practitioner and specialty hepatology shared-care (HEPREACH) clinic in Brisbane, Australia. Patient-reported data on health literacy and clinical information from adult patients (n = 66) of CALD background recruited from the liver clinic were analyzed. Health literacy was assessed using a 5-question, 12-point scale. Variance weighted multiple linear regression was used to identify factors associated with knowledge about VH. About three-quarters of patients (74.2%) were diagnosed with hepatitis B. The median knowledge score was 7.8 (interquartile range [IQR] 6‒9). One in five patients did not understand the infective nature of VH, 30.3% did not understand mother-to-child transmission risk, and 30-40% of patients thought activities such as kissing, sharing food or mosquito bites could spread VH. Only 6% of patients understood the risk of liver cancer and the need for regular screening. Higher educational level (secondary, β = 4.8, p < 0.0001 or tertiary, β = 8.1, p < 0.0001 vs. primary) was associated with better knowledge, and transition through a refugee camp (vs. not, β = - 1.2, p = 0.028) and country of diagnosis (overseas vs. Australia, β = - 1.9, p = 0.016) were associated with poorer knowledge. Country of origin, refugee status and opportunities for tertiary education impact patients' understanding of VH. Ensuring delivery of culturally appropriate care and education is critical to improve knowledge, reduce misconceptions to improve care and outcomes for VH in CALD migrant communities.

Trends in chronic hepatitis B prevalence in Australian women by country of birth, 2000 to 2016

Routine antenatal screening for chronic hepatitis B (HBV) in countries with high migrant populations provides an opportunity to monitor trends in HBV prevalence and can inform estimates locally and in countries with limited seroprevalence data. We linked perinatal birth register records with HBV notifications in the largest Australian state, over the period 2000-2016. Among women aged 15-44 years, we estimated age-standardized chronic HBV prevalence overall and by country of birth and also estimated trends in age-standardized HBV prevalence over time using regression modelling. Among 903 831 women, 8001 linked to a chronic HBV infection record (overall age-standardized prevalence 0.76%, 95% CI: 0.74-0.78). Prevalence varied by country of birth with the highest estimates among women born in Sierra Leone (11.13%, 95% CI: 8.29-13.96), Taiwan (8.08%, 95% CI: 6.74%-9.43%), Cambodia (7.47%, 95% CI: 6.50%-8.45%) and Vietnam (7.36%, 95% CI: 6.97%-7.75%); more moderate estimates among women from North Korea (2.76%, 95% CI: 1.99-3.53) and Samoa (2.64%, 95% CI: 1.99%-3.29%); prevalence was 0.18% (95% CI: 0.17-0.19) in Australian-born women. Over 17 years, there were significant reductions in HBV prevalence among all women (from 0.88% in 2000 to 0.57% in 2016; P < .0001). Among women from high prevalence countries, the greatest absolute reductions were observed among those from Taiwan (10.1%, P < .001) followed by Tonga (5.4%, P < .001), whereas no reductions were observed for women born in Vietnam (P = .08), South Korea (P = .41) and Sudan (P = .06). In conclusion, routine antenatal HBV testing can be used to inform HBV prevalence estimates and vaccine programme impact in countries with limited surveillance and high migration to Australia.

Catching up with catch-up: a policy analysis of immunisation for refugees and asylum seekers in Victoria

This study examines catch-up immunisation for people of refugee-like background in Victoria, exploring effective models of service delivery to complete catch-up vaccinations. The analysis is based on: (i) review of the medical literature, Commonwealth and Victorian government immunisation policy and immunisation patient information; (ii) review of vaccination coverage and service delivery data; and (iii) stakeholder interviews completed in 2014 with 45 people from 34 agencies, including 9 local government areas in Victoria. Although refugees and asylum seekers all need catch-up vaccinations on arrival, they face significant barriers to completing immunisation in Australia. Analysis suggests missed opportunities by service providers and perceptions that catch-up vaccination is time-consuming, difficult and resource-intensive. Service delivery is fragmented across primary care and local government, and pathways depend on age, location and healthcare access. There are strengths, but also limitations in all current service delivery models. Gaps in vaccine funding for refugee-like populations have now been addressed through Commonwealth initiatives, however migration is still not well considered in immunisation policy, and existing systems for notification payments do not capture catch-up vaccination for these groups. Providers identify areas for improvement in professional development and support, patient information, patient-held records and immunisation surveillance data.

Aiming for the elimination of viral hepatitis in Australia, New Zealand, and the Pacific Islands and Territories: Where are we now and barriers to meeting World Health Organization targets by 2030

Viral hepatitis affects more than 320 million people globally, leading to significant morbidity and mortality due to liver failure and hepatocellular carcinoma (HCC). More than 248 million people (3.2% globally) are chronically infected with hepatitis B virus (HBV), and an estimated 80 million people (1.1% globally) are chronically infected with hepatitis C virus (HCV). In 2015, more than 700 000 deaths were directly attributable to HBV, and nearly 500 000 deaths were attributable to HCV infection; 2-5% of HBV-infected people develop HCC per annum irrespective of the presence of cirrhosis, whereas 1-5% HCV-infected people with advanced fibrosis develop HCC per annum. The rapidly escalating global mortality related to HBV and HCV related viral hepatitis to be the 7th leading cause of death worldwide in 2013, from 10th leading cause in 1990. Australia, New Zealand, and Pacific Island Countries and Territories fall within the World Health Organization Western Pacific Region, which has a high prevalence of viral hepatitis and related morbidity, particularly HBV. Remarkably, in this region, HBV-related mortality is greater than for tuberculosis, HIV infection, and malaria combined. The region provides a unique contrast in viral hepatitis prevalence, health system resources, and approaches taken to achieve World Health Organization global elimination targets for HBV and HCV infection. This review highlights the latest evidence in viral hepatitis epidemiology and explores the health resources available to combat viral hepatitis, focusing on the major challenges and critical needs to achieve elimination in Australia, New Zealand, and Pacific Island Countries and Territories.

Analytical and field evaluation of the Biocentric Generic HCV assay on open polyvalent PCR platforms in France and Cambodia

BACKGROUND

Implementation of affordable methods for HCV viremia is a key priority for identifying individuals who need treatment among persons screened positive for HCV antibodies. Different HCV PCR assays for use on open polyvalent PCR platforms are currently commercially available but studies evaluating the performances of these nucleic acid tests are needed.

OBJECTIVES

In the present study, we evaluated the analytical and clinical performances of a recently developed HCV RNA PCR assay for detection and quantification of HCV viremia.

STUDY DESIGN

In this study the Biocentric Generic HCV PCR was compared to the Roche Cobas AmpliPrep/Cobas TaqMan HCV RNA assay. Analytical and clinical performances was evaluated on reference materials and HCV plasma samples collected in 141 patients attending at the Montpellier University Hospital in France. Field evaluation was performed on samples collected in 185 patients attending at Medical Laboratory, Institut Pasteur in Cambodia.

RESULTS

The lower limit of detection ranged from 50 HCV RNA IU/ml to 300 HCV RNA IU/ml using four different Diasorin and Qiagen automated or manual extraction methods. The specificity (CI) and sensitivity of the assay were 100% (92.5-100), and 98.7% (92.3-99.9), respectively, in France, and 100% (95.5-100), and 100% (94.4-100%), respectively, in Cambodia. Bland-Altman analysis shown good agreement between the two assays including for genotypes 6 HCV, which represent the majority of HCV isolates in Cambodia.

CONCLUSIONS

The Biocentric Generic HCV assay has shown overall satisfactory analytical performances and a close agreement to the Cobas HCV assay on clinical specimens collected in France and Cambodia. There is an urgent need to further evaluate commercial assays dedicated to HCV detection and quantification using open polyvalent PCR platforms in different settings.

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.

Long-term impact of childhood hepatitis B vaccination programs on prevalence among Aboriginal and non-Aboriginal women giving birth in Western Australia

BACKGROUND/AIMS

To evaluate the long-term effect of infant and childhood hepatitis B (HBV) vaccination programs among birthing women in Western Australia.

METHODS

A cohort of Western Australian women born from 1974 to 1995 was created using Birth Registrations and Electoral Roll records. They were linked to a perinatal register and notifiable diseases register to identify women having respectively their first births between 2000 and 2012 and diagnoses of HBV infections. HBV prevalence was estimated in Aboriginal and non-Aboriginal women, and according to maternal birth year cohorts.

RESULTS

Of 66,073 women, 155 (0.23%) had a linked non-acute HBV notification. HBV prevalence was five times higher in Aboriginal women compared to their non-Aboriginal counterparts (0.92%, 95%CI 0.65-1.18 versus 0.18%, 0.15-0.21). Among Aboriginal women, after adjusting for year of giving birth and region of residence, those born in the targeted infant and school-based vaccination era (maternal year of birth 1988-1995) had an 89% lower risk (adjusted odds ratio [aOR] 0.11, 0.04-0.33) of HBV than those born in the pre-vaccination era (1974-1981). Prevalence also differed between Aboriginal women residing in rural/remote areas compared to those in major cities (aOR 3.06, 1.36-6.88). Among non-Aboriginal women, no significant difference in HBV prevalence was observed by maternal birth cohort (p = 0.20) nor by residence (p = 0.23), but there were significant differences by ethnicity with a 36-fold higher prevalence (aOR 36.08, 22.66-57.46) in non-Caucasian versus Caucasian women.

CONCLUSIONS

A significant decline in HBV prevalence in Aboriginal birthing mothers was observed following the introduction of HBV vaccination programs in Western Australia. There were also considerable disparities in prevalence between women by area of residence and ethnicity. Our findings reflect those observed in women in other Australian jurisdictions. Continued surveillance of HBV prevalence in birthing mothers will provide ongoing estimates of HBV vaccination program impact across Australia and the populations most at risk of chronic HBV.

Improving access to health care for chronic hepatitis B among migrant Chinese populations: A systematic mixed methods review of barriers and enablers

Migrant Chinese populations in Western countries have a high prevalence of chronic hepatitis B but often experience poor access to health care and late diagnosis. This systematic review aimed to identify obstacles and supports to timely and appropriate health service use among these populations. Systematic searches resulted in 48 relevant studies published between 1996 and 2015. Data extraction and synthesis were informed by models of healthcare access that highlight the interplay of patient, provider and health system factors. There was strong consistent evidence of low levels of knowledge among patients and community members; but interventions that were primarily focused on increasing knowledge had only modest positive effects on testing and/or vaccination. There was strong consistent evidence that Chinese migrants tend to misunderstand the need for health care for hepatitis B and have low satisfaction with services. Stigma was consistently associated with hepatitis B, and there was weak but consistent evidence of stigma acting as a barrier to care. However, available evidence on the effects of providing culturally appropriate services for hepatitis B on increasing uptake is limited. There was strong consistent evidence that health professionals miss opportunities for testing and vaccination. Practitioner education interventions may be important, but evidence of effectiveness is limited. A simple prompt in patient records for primary care physicians improved the uptake of testing, and a dedicated service increased targeted vaccination coverage for newborns. Further development and more rigorous evaluation of more holistic approaches that address patient, provider and system obstacles are needed.

Trends in the prevalence of hepatitis B infection among women giving birth in New South Wales

OBJECTIVES

To evaluate the effect of targeted and catch-up hepatitis B virus (HBV) vaccination programs in New South Wales on HBV prevalence among women giving birth for the first time.

DESIGN

Observational study linking data from the NSW Perinatal Data Collection for women giving birth during 2000-2012 with HBV notifications in the NSW Notifiable Conditions Information Management System.

MAIN OUTCOME MEASURES

HBV prevalence in Indigenous Australian, non-Indigenous Australian-born, and overseas-born women giving birth.

RESULTS

Of 482 944 women who gave birth to their first child, 3383 (0.70%) were linked to an HBV notification. HBV prevalence was 1.95% (95% CI, 1.88-2.02%) among overseas-born women, 0.79% (95% CI, 0.63-0.95%) among Indigenous Australian women, and 0.11% (95% CI, 0.09-0.12%) among non-Indigenous Australian-born women. In Indigenous Australian women, prevalence was significantly lower for those who had been eligible for inclusion in the targeted at-risk newborn or universal school-based vaccination programs (maternal year of birth, 1992-1999: 0.15%) than for those who were not (born ≤ 1981: 1.31%; for trend, P < 0.001). There was no statistically significant downward trend among non-Indigenous Australian-born or overseas-born women. HBV prevalence was higher among Indigenous women residing in regional and remote areas than those in major cities (adjusted odds ratio [aOR], 2.23; 95% CI, 1.40-3.57), but lower for non-Indigenous (aOR, 0.39; 95% CI, 0.28-0.55) and overseas-born women (aOR, 0.61; 95% CI, 0.49-0.77).

CONCLUSION

Among women giving birth, there was a significant reduction in HBV prevalence in Indigenous women associated with the introduction of the HBV vaccination program in NSW, although prevalence remains higher than among non-Indigenous Australian-born women, and it also varies by region of residence. Continuing evaluation is needed to ensure that the prevalence of HBV infections continues to fall in Australia.

Regional challenges: evaluation of a hepatitis outreach programme using transient elastography (FibroScan) in Victoria

BACKGROUND

Evaluation of an outreach programme using a mobile transient elastography (TE) device (FibroScan) to improve liver disease assessment in different clinical settings.

AIMS

To evaluate a programme of liver fibrosis assessment by TE and to compare fibrosis scores between different sites and patient groups.

METHODS

Prospective cohort study. TE was conducted at a tertiary hospital and during outreach clinics in three different settings: community clinics, clinics for people who use drugs (PWUD) and regional clinics in rural Victoria. All patients referred for TE at the participating locations were eligible during the study period.

RESULTS

A total of 200 of 623 patients was assessed and evaluated during outreach sessions (regional 100; PWUD 18; community 82). While the majority of patients in community centres were infected with hepatitis B (68%), most patients in regional clinics and in PWUD settings had hepatitis C virus (HCV) (81 and 100%, respectively). Significantly more patients assessed at regional clinics and PWUD settings presented with severe fibrosis (F3-F4, F4): regional clinics 39%; PWUD 31%; tertiary 11%; community 7%, (P <0.001). Multivariable logistic regression analysis revealed that older age, alcohol consumption, male sex, increased alanine transferase levels, HCV infection and importantly, evaluation at regional sites were independently associated with severe fibrosis.

CONCLUSIONS

A TE-based outreach programme allows for assessment of liver fibrosis in varied and regional populations. The finding that patients in regional settings and PWUD presented with more advanced fibrosis should prompt improvements in healthcare to improve access for these populations.

Epidemiological study of hepatitis B and C in a municipality with rural characteristics: Cássia dos Coqueiros, State of São Paulo, Brazil

INTRODUCTION

Hepatitis B and C viral infections remain an important cause of global morbidity and mortality. Studies have been conducted in population groups of large cities, leaving gaps in the knowledge regarding the situation in small municipalities. We aimed to measure the prevalence of hepatitis B and C markers and presence of infection-associated factors.

METHODS

All inhabitants of Cássia dos Coqueiros aged ≥18 years who agreed to participate in the research were included. We collected blood as well as information via a questionnaire between March 2011 and December 2013. Univariate and multivariate analyses were conducted.

RESULTS

Among the 1,001 participants, 41 (4.1%) participants had a serological profile of hepatitis B viral exposure, and only one (0.1%) participant was considered a virus carrier. The frequency of isolated antibody to hepatitis B virus surface antigen (anti-HBs) markers was 17.8% for the overall population. In the multivariate analysis, hepatitis B virus (HBV) infection was associated with age, birth outside the State of São Paulo, history of hepatitis, ≥2 sexual partners in the last 6 months, and tattoos. Four (0.4%) participants had a serological profile of hepatitis C viral exposure. However, after confirmation using viral ribonucleic acid (RNA) evaluation, only one (0.1%) individual remained positive.

CONCLUSIONS

The positivity rates for hepatitis B and C were low, despite greater sexual freedom and the recent emergence of illicit drugs, as observed by the health personnel working in Cássia dos Coqueiros.

Seroprevalence, genotypic distribution and potential risk factors of hepatitis B and C virus infections among adults in Siem Reap, Cambodia

AIM

We investigated hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among adults in Siem Reap, Cambodia, to consider the prevention strategy in cooperation with the Ministry of Health in Cambodia.

METHODS

Serological tests for determining HBV and HCV infections and questionnaires were performed from 2010 to 2012 among the general population in the province of Siem Reap. Multivariate logistic regression analysis was conducted to clarify the factors related to HBV and HCV infections.

RESULTS

There were 483 participants, comprising 194 men and 289 women (age range, 18-89 years). The prevalence of hepatitis B surface antigen was not very high at 4.6%, while anti-hepatitis B core (anti-HBc) was high at 38.5%. All HBV DNA samples were classified as genotype C. Anti-HBc showed the trend that the older the age, the higher the positive rate (P = 0.0002). The prevalence of HCV RNA and anti-HCV were 2.3% and 5.8%, respectively. HCV RNA was detected in 39.3% of anti-HCV positive samples and most of them were classified as genotype 6 (54.5%) and 1 (27.3%). Remarkably, in multivariate logistic regression analysis, history of operation and blood transfusion were significantly associated with the positivity for HBV infection and HCV RNA, respectively.

CONCLUSION

Our results showed that operation and blood transfusion were potential risk factors for HBV and HCV infection, respectively, and supposed that horizontal HBV transmission may be frequent in adults in Cambodia. Hence, for reducing HBV and HCV infections, it is necessary to improve the safety of blood and medical treatment.

Epidemiology of Viral Hepatitis and Liver Diseases in Cambodia

In Cambodia, the true burden of viral hepatitis has not been revealed, but many surveys were carried out focusing on specific population or on small scales. Different markers of viral hepatitis were found between 27 and 97% in children and almost 100% in adults. Viral hepatitis B in children was 3.5% in 2006 and dropped in 2011; and in adults, it ranged from 4.5 to 10.8%. Viral hepatitis C was between 0.87 and 14.7%. No data are available for hepatitis D in the country. Viral hepatitis E (anti-HEV IgG) went from 7.2 to 12.7%. The complications due to viral hepatitis including chronic liver diseases and hepatocellular carcinoma were reported in the health information system. Around 79% of the patients with high transaminase had at least one viral marker and about 45% of the adults with chronic hepatitis and liver cirrhosis were positive for Hepatitis B surface antigen (HBsAg). Hepatocellular carcinoma accounted for 19.1% of all reported cancer cases. Hepatitis B surface antigen was found in between 55 and 90% in adults with hepatocellular carcinoma and anti-HCV in one-fourth. The only intervention implemented in Cambodia is vaccination against viral hepatitis B (HepB vaccine).

How to cite this article

Sreng B, Kimcheng HOK, Sovann LY, Huot ENG. Epidemiology of Viral Hepatitis and Liver Diseases in Cambodia. Euroasian J Hepato-Gastroenterol 2015;5(1):30-33.

Molecular epidemiology of hepatitis B virus in Asia

Although safe and effective vaccines against hepatitis B virus (HBV) have been available for three decades, HBV infection remains the leading cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma (HCC) worldwide, especially in Asian countries. HBV has been classified into at least 9 genotypes according to the molecular evolutionary analysis of the genomic DNA sequence and shown to have a distinct geographical distribution. Novel HBV genotypes/subgenotypes have been reported, especially from Southeast Asian countries. The clinical characteristics and therapeutic effectiveness of interferon (IFN) and nucleos(t)ide analogues vary among different HBV genotypes. Mutations at T1653C in subgenotype C2 from Japan and South Korea, C/A1753T and C1858T in subgenotype C1 from Vietnam, and C1638T and T1753V in subgenotype B3 from Indonesia were reported to be associated with advanced liver diseases including HCC. Genotype distribution in Japan has been changed by an increasing ratio of subgenotype A2 in chronic hepatitis B. While a large number of epidemiological and clinical studies have been reported from Asian countries, most of the studies were conducted in developed countries such as Taiwan, China, South Korea and Japan. In this review, the most recent publications on the geographical distribution of genetic variants of HBV and related issues such as disease progression and therapy in Asia are updated and summarized.