A re-assessment of the epidemiology and patient characteristics of hepatitis D virus infection in inner city London

Low coverage of hepatitis D virus testing in individuals with hepatitis B virus and HIV, the Netherlands, 2000 to 2022

BackgroundSince 2009, European guidelines recommend individuals with hepatitis B virus (HBV) and HIV be tested for hepatitis D virus (HDV).AimTo analyse HDV testing in individuals with HBV/HIV during routine practice in the Netherlands.MethodsWe assessed data from the ATHENA cohort of people with HIV who were ever HBV surface antigen-positive, aged ≥ 18 years and attended one of 24 HIV treatment centres in the Netherlands during 2000-22. Using longitudinal analysis, we estimated the percentage of individuals ever tested for HDV (antibody or RNA test) over time. In cross-sectional analysis, determinants for ever being tested by end of follow-up were assessed using relative risk regression.ResultsWe identified 1,715 individuals with HBV/HIV; 1,460 (85.1%) and 255 (14.9%) were male and female at birth, respectively (median age: 52 years; IQR: 42-59). Only 249 (14.5%) had an HDV test. The percentage tested increased from 5.0% (95% CI: 3.4-7.3) in 2000 to 17.0% (95% CI: 14.9-19.3) in 2022. In 2022, 16.2% (95% CI: 13.7-19.1) of men who have sex with men, 25.0% (95% CI: 9.7-50.9) of persons who inject(ed) drugs and 18.1% (95% CI: 14.6-22.3) of heterosexual/others were tested. In multivariable analysis, ever having an HDV test was associated with detectable HBV DNA viral load (p < 0.001), ever presenting with elevated alanine aminotransferase (ALT) levels (p = 0.023), advanced fibrosis/cirrhosis (p = 0.001) and being overweight/obese (p = 0.043).ConclusionsHDV testing coverage in the Netherlands is low for individuals with HBV/HIV. Although testing was more common in those with advanced liver disease, a considerable proportion at risk of HDV still need testing.

Epidemiology of hepatitis D virus infection in Europe: Is it vanishing?

Co-infection with hepatitis delta virus (HDV) is a challenging health care problem worldwide, estimated to occur in approximately 5%-10% of patients with chronic hepatitis B virus (HBV) infection. While HBV prevalence is decreasing globally, the prevalence of HDV infection is rising in some parts mainly due to injection drug use, sexual transmission and immigration from high endemicity areas. Eastern Europe and the Mediterranean are among the regions with high rates of endemicity for HDV and the immigration from high endemicity areas to Central and Western Europe has changed the HDV epidemiology. We aimed to review the prevalence of HDV infection in Europe. A paucity of publication appears in many European countries. Prevalence studies from some countries are old dated and some other countries did not report any prevalence studies. The studies are accumulated in few countries. Anti-HDV prevalence is high in Greenland, Norway, Romania, Sweden and Italy. Belgium, France, Germany, Spain, Switzerland, Turkey and United Kingdom reported decreasing prevalences. Among cirrhotic HBV patients, Germany, Italy and Turkey reported higher rates of HDV. The studies including centres across the Europe reported that HIV-HBV coinfected individuals have higher prevalence of HDV infection. The immigrants contribute the HDV infection burden in Greece, Italy, and Spain in an increasing rate. Previous studies revealed extremely high rates of HDV infection in Germany, Greece, Italy and Sweden. The studies report a remarkably high prevalence of hepatitis delta among HIV/HBV-coinfected individuals, individuals who inject drugs, immigrants and severe HBV infected patients across Europe. The HDV infection burden still appears to be significant. In the lack of an effective HDV therapy, prevention strategies and active screening of HBV/HDV appear as the most critical interventions for reducing the burden of liver disease related to HDV infection in Europe.

Epidemiology Pattern, Prevalent Genotype Distribution, Fighting Stigma and Control Options for Hepatitis D in Bulgaria and Other European Countries

Hepatitis D virus (HDV) is a satellite virus that causes the most aggressive form of all viral hepatitis in individuals already infected with HBV (hepatitis B virus). In recent years, there has been a negative trend towards an increase in the prevalence of chronic hepatitis D in Europe, especially among immigrant populations coming from regions endemic for the virus. The aim of this review is to analyse the current epidemiology of chronic HDV, routes of transmission, prevalent genotype, its management, prevention, fighting stigma and options for viral control in European countries, such as Bulgaria.

Global Distribution and Natural Recombination of Hepatitis D Virus: Implication of Kyrgyzstan Emerging HDVs in the Clinical Outcomes

Discrepancies in human hepatitis delta virus (HDV) genotypes impact the virus’ biological behavior, clinical manifestation, and treatment response. Herein, this report aims to explore the role of recombination in the worldwide genotypic distribution and genetic diversity of HDV. Three-hundred-forty-eight human HDV full-length genomic sequences of ~1678 nt in length, isolated in twenty-eight countries worldwide between 1986 and 2018, were analysed. Similarity analysis and recombination mapping were performed, and forty-eight recombination events were identified, twenty-nine of which were isolated from Kyrgyzstan and determined to be involved in the diversity and extension of HDV sub-genotypes. HDV recombination occurred only between the genetically close genotypes (genotype 5 and genotype 2) or mainly within genotype 1, suggesting the complex replicative molecular mechanisms of HDV-RNA. The global distribution and classification of HDV genotypes have been updated, indicating that HDV recombination is one of the driving forces behind the biodiversity and the evolution of human HDV genomes. The outcome analysis suggests that the expansion of HDV sub-genotypes and the complex recombination networks might be related to the genomic character of Kyrgyzstan circulating strains and extensive mobility within countries and across borders. These findings will be of great importance in formulating more effective public health HDV surveillance strategies and guiding future molecular and epidemiological research to achieve better clinical outcomes.

Hepatitis B virus/hepatitis D virus epidemiology: Changes over time and possible future influence of the SARS-CoV-2 pandemic

Hepatitis D virus (HDV) is a defective liver-tropic virus that needs the helper function of hepatitis B virus (HBV) to infect humans and replicate. HDV is transmitted sexually or by a parenteral route, in co-infection with HBV or by super-infection in HBV chronic carriers. HDV infection causes acute hepatitis that may progress to a fulminant form (7%-14% by super-infection and 2%-3% by HBV/HDV co-infection) or to chronic hepatitis (90% by HDV super-infection and 2%-5% by HBV/HDV co-infection), frequently and rapidly progressing to cirrhosis or hepatocellular carcinoma (HCC). Peg-interferon alfa the only recommended therapy, clears HDV in only 10%-20% of cases and, consequently, new treatment strategies are being explored. HDV endemicity progressively decreased over the 50 years from the identification of the virus, due to improved population lifestyles and economic levels, to the use of HBV nuclei(t)side analogues to suppress HBV replication and to the application of universal HBV vaccination programs. Further changes are expected during the severe acute respiratory syndrome coronavirus-2 pandemic, unfortunately towards increased endemicity due to the focus of healthcare towards coronavirus disease 2019 and the consequently lower possibility of screening and access to treatments, lower care for patients with severe liver diseases and a reduced impulse to the HBV vaccination policy.

Hepatitis D virus seroprevalence in Egyptian HBsAg-positive children: a single-center study

In this study, we investigated the seroprevalence of anti-hepatitis D virus (HDV) antibodies in hepatitis B surface antigen (HBsAg)-positive children after 25 years of obligatory vaccination of infants against hepatitis B virus. This cross-sectional study included 120 treatment-naïve HBsAg-positive children, with a male-to-female ratio of 1.8:1 and a mean age of 7.8 ± 3.8 years (range, 1-17 years). Mothers were positive for HBsAg in 96.6% of the cases. HBeAg-positive chronic infection was observed in 60% of the cases, HBeAg-positive chronic hepatitis in 12.5%, and HBeAg-negative chronic infection in 26.7%. Anti-HDV antibodies were not detected in any of the cases. Thus, there is a lack of anti-HDV antibodies in HBsAg-positive children, despite the current burden in adults.

HDV infection in immigrant populations

AIMS

Little data have been published so far on the epidemiological aspects of hepatitis D virus (HDV) infection in immigrant populations and even poorer is the information on the virological, phylogenetic, and clinical aspects of this infection in these populations. This review article, aimed primarily at physicians caring for immigrants, summarizes the information available on HDV infection and analyzes data on this topic concerning the immigrant populations.

METHODS AND RESULTS

The prevalence of HDV infection in HBsAg-positive immigrants varies according to the country of origin. For example, in immigrants from sub-Saharan Africa, this prevalence is higher in those born in Equatorial Guinea (24.4%) than those from other African countries (10.3%). The epidemiological impact of HDV infection linked to migratory flows is a function of the different endemicity between countries of origin and countries in which a new existence has been established. This impact is high when immigrants from areas endemic to HDV infection (eg, Equatorial Guinea) settle in areas of low endemicity (eg, Germany or England, with a prevalence of around 4%), while the impact is lesser or nonexistent if the migratory flows are directed toward countries with intermediate endemicity (eg, Italy and Greece, with a prevalence of around 10%).

CONCLUSION

This impact of immigration on HDV epidemiology can be strong when HDV endemicity is high in the country of origin and low in the host country and slight when immigrants move to high or medium endemic countries.

Hepatitis delta infection - Current and new treatment options

In humans, hepatitis D virus (HDV) infection only occurs in the presence of a concomitant hepatitis B virus (HBV) infection, and induces the most severe form of human viral hepatitis. Even though HDV is spread worldwide and is endemic in some regions, screening and treatment has been often neglected in part due to the lack of an effective therapy. Moreover, HDV prevalence rates are increasing in many countries driven by immigration from areas of high endemicity. Currently, no FDA-approved anti-HDV therapy is available, although interferon (IFN) alpha therapy has demonstrated benefit in a minority of patients. In this review, we present a current view of our understanding of the epidemiology, molecular virology and management of HDV infection. We additionally discuss new treatment approaches in development and describe the most promising results of recent and ongoing clinical trials of these new potential agents.

Molecular epidemiology of hepatitis B virus infection in Switzerland: a retrospective cohort study

BACKGROUND

Chronic hepatitis B virus (HBV) infection affects up to 7% of the European population. Specific HBV genotypes are associated with rapid progression to end-stage liver disease and sub-optimal interferon treatment responses. Although the geographic distribution of HBV genotypes differs between regions, it has not been studied in Switzerland, which lies at the crossroads of Europe.

METHODS

In a retrospective analysis of 465 HBV samples collected between 2002 and 2013, we evaluated the HBV genotype distribution and phylogenetic determinants, as well as the prevalence of serological evidence of hepatitis delta, hepatitis C and HIV infections in Switzerland. Baseline characteristics of patients were compared across their region of origin using Fisher's exact test and ANOVA, and risk factors for HBeAg positivity were assessed using logistic regression.

RESULTS

The Swiss native population represented 15.7% of HBV-infected patients living in Switzerland. In the overall population, genotype D was most prevalent (58.3%), whereas genotype A (58.9%) was the predominant genotype among the Swiss native population. The prevalence of patients with anti-HDV antibodies was 4.4%. Patients of Swiss origin were most likely to be HBeAg-positive (38.1%). HBV genotypes of patients living in Switzerland but sharing the same original region of origin were consistent with their place of birth.

CONCLUSIONS

The molecular epidemiology of HBV infection in Switzerland is driven by migration patterns and not by the genotype distribution of the native population. The prevalence of positive anti-HDV antibodies in our cohort was very low.

Delta hepatitis within the Veterans Affairs medical system in the United States: Prevalence, risk factors, and outcomes

BACKGROUND & AIMS

Low hepatitis delta prevalence estimates in the United States are likely biased due to low testing rates. The objectives of this study were to quantify the prevalence of testing and identify factors associated with hepatitis D positive status among chronic hepatitis B patients in the Veterans Health Administration.

METHODS

We performed a nationwide retrospective study of all veterans who tested positive for HBsAg from October 1999 to December 2013. Hepatitis D antibody testing results were used to stratify patients into three groups: HDV-positive, HDV-negative, and HDV-not tested. Demographics, comorbidities, additional laboratory data and clinical outcomes were compared across these groups of patients using standard statistical approaches.

RESULTS

Among 25,603 patients with a positive hepatitis B surface antigen, 2175 (8.5%) were tested for HDV; 73 (3.4%) patients tested positive. Receiving HDV testing was associated with receipt of testing for HBV, HIV, and HCV. Predictors of positive HDV results included substance abuse and cirrhosis. Fitting a predefined high-risk profile (abnormal ALT with suppressed HBV DNA titers) was strongly associated with testing positive for HDV (OR 3.2, 95%CI 1.4-7.5). Most (59%) of HDV-positive patients were HCV co-infected. HDV-positive subjects had higher risks of all-cause mortality. Incidence rates of HCC were 2.9 fold higher in HDV-positive relative to HDV-negative individuals (p=0.002). In adjusted analyses, HDV was independently associated with HCC (OR 2.1, 95%CI 1.1-3.9).

CONCLUSIONS

Testing rates for hepatitis delta in chronic hepatitis B patients in the United States are inappropriately low. Approaches to increase testing for HDV particularly in high-risk subsets should be explored.

Hepatitis delta virus testing, epidemiology and management: a multicentre cross-sectional study of patients in London

BACKGROUND

Hepatitis delta virus (HDV) testing is recommended for all patients with hepatitis B virus (HBV) infection. HDV infection is associated with severe liver disease and interferon is the only available treatment.

OBJECTIVES

To determine the rate of anti-HDV antibody testing in HBV patients; and to describe the epidemiology, clinical characteristics and management of HDV-infected patients at four hospitals in London.

STUDY DESIGN

The anti-HDV testing rate was estimated by reviewing clinical and laboratory data. Cross-sectional data collection identified HDV-infected patients who had attended the study centres between 2005 and 2012.

RESULTS

At a centre with clinic-led anti-HDV testing, 40% (67/168) of HBV patients were tested. Recently diagnosed HBV patients were more likely to be screened than those under long-term follow-up (62% vs 36%, P=0.01). At a centre with reflex laboratory testing, 99.4% (3543/3563) of first hepatitis B surface antigen positive samples were tested for anti-HDV. Across the four study centres there were 55 HDV-infected patients, of whom 50 (91%) had immigrated to the UK and 27 (49%) had evidence of cirrhosis. 31 patients received interferon therapy for HDV with an end of treatment virological response observed in 10 (32%).

CONCLUSIONS

The anti-HDV testing rate was low in a centre with clinic-led testing, but could not be evaluated in all centres. The HDV-infected patients were of diverse ethnicity, with extensive histological evidence of liver disease and poor therapeutic responses. Future recommendations include reflex laboratory testing algorithms and a prospective cohort study to optimise the investigation and management of these patients.

Increasing incidence of recent hepatitis D virus infection in HIV-infected patients in an area hyperendemic for hepatitis B virus infection

BACKGROUND

Superinfection with hepatitis D virus (HDV) may increase the risk for hepatitis flares and chronic hepatic complications in patients with chronic hepatitis B virus (HBV) infection. This retrospective observational study aimed to examine the incidence of and factors associated with recent HDV superinfection among individuals coinfected with human immunodeficiency virus (HIV) and HBV.

METHOD

Anti-HDV immunoglobulin G (IgG) was sequentially determined in 375 HIV/HBV-coinfected patients to estimate the HDV incidence between 1992 and 2012. Plasma HDV and HBV loads and HBV surface antigen (HBsAg) levels were determined for the HDV seroconverters. A nested case-control study was conducted to identify the associated factors with HDV seroconversion. Phylogenetic analysis was performed using HDV sequences amplified from HDV seroconverters and HDV-seropositive patients at baseline.

RESULTS

During 1762.4 person-years of follow-up [PYFU], 16 patients seroconverted for HDV, with an overall incidence rate of 9.07 per 1000 PYFU, which increased from 0 in 1992-2001, to 3.91 in 2002-2006, to 13.26 per 1000 PYFU in 2007-2012 (P < .05). Recent HDV infection was associated with elevated aminotransferase and bilirubin levels and elevated rapid plasma reagin titers. Of the 12 patients with HDV viremia, 2 were infected with genotype 2 and 10 with genotype 4. HBsAg levels remained elevated despite a significant decline of plasma HBV DNA load with combination antiretroviral therapy that contained lamivudine and/or tenofovir.

CONCLUSIONS

Our findings show that the incidence of recent HDV infection in HIV/HBV-coinfected patients increased significantly from 1992-2001 to 2007-2011, and was associated with hepatitis flares and syphilis.

Hepatitis delta: epidemiology, diagnosis and management 36 years after discovery

With recent studies showing increased prevalence of hepatitis delta (HDV) even in the US, Australia, and some countries in Europe, and very high prevalence in endemic regions, HDV infection is far from being a disappearing disease. Although immigrants from endemic countries have been shown to have increased risk, studies have clearly shown that the disease is not solely appearing in traditional high-risk groups. Recent studies provide increasing evidence that sexual transmission may be an important factor in HDV infection spread. Based on the totality of evidence showing increased disease progression and substantially increased risk of cirrhosis in HDV-infected CHB patients, and the current studies showing higher than expected prevalence, it is time to call for HDV screening of all CHB patients. HDV viral load detection and measurement should be considered in all patients whether or not they are anti-HDV-positive. With universal screening of CHB patients for HDV, earlier diagnosis and consideration of treatment would be possible. Current treatment of HDV is IFN-based therapy with or without HBV antivirals, but current research indicates the possibility that prenylation inhibitors, entry inhibitors, HBsAg release inhibitors, or other therapies currently in the pipeline may provide more effective therapy in the future. In addition, universal screening would serve the important public health goal of allowing patients to be educated on their status and on the need for HDV-negative patients to protect themselves against superinfection and for HDV-infected patients to protect against transmission to others. Further studies and global awareness of HDV infection are needed.