Hepatitis Delta Virus Clade 8 Is the Predominant Clade Circulating in Botswana amongst People Living with HIV.

Hepatitis delta virus (HDV) co-infections more often result in severe hepatitis compared to hepatitis B virus (HBV) infections alone. Despite a high HDV prevalence (7.1%), information regarding circulating HDV clades is very limited in Botswana. We extracted total nucleic acid from confirmed HDV-positive samples and quantified their viral load. We then sequenced the large hepatitis delta antigen (L-HDAg) using Oxford Nanopore Technology (ONT). Genotyping was performed using the HDV Database, and HDV mutation profiling was performed on AliView. All participants with HBV genotypic information belonged to sub-genotype A1, and 80% (4/5) of them had a higher HDV viral load and a lower HBV viral load. We sequenced 75% (9/12) of the HDV-positive samples, which belonged to HDV clade 8. A total of 54 mutations were discovered, with the most prevalent being Q148R (16%), D149P (16%) and G151D (16%). Known mutations such as S117A, K131R, R139K and G151D were detected, while the other mutations were novel. Our results reveal that HDV clade 8 is the predominant clade in Botswana. The significance of all mutations remains unclear. Future studies with a larger sample size to detect other HDV clades that might be circulating in Botswana and functionally characterize the detected mutations are warranted.

Hepatitis B virus entry, assembly, and egress.

SUMMARYHepatitis B virus (HBV) is an important human pathogen that chronically infects approximately 250 million people in the world, resulting in ~1 million deaths annually. This virus is a hepatotropic virus and can cause severe liver diseases including cirrhosis and hepatocellular carcinoma. The entry of HBV into hepatocytes is initiated by the interaction of its envelope proteins with its receptors. This is followed by the delivery of the viral nucleocapsid to the nucleus for the release of its genomic DNA and the transcription of viral RNAs. The assembly of the viral capsid particles may then take place in the nucleus or the cytoplasm and may involve cellular membranes. This is followed by the egress of the virus from infected cells. In recent years, significant research progresses had been made toward understanding the entry, the assembly, and the egress of HBV particles. In this review, we discuss the molecular pathways of these processes and compare them with those used by hepatitis delta virus and hepatitis C virus , two other hepatotropic viruses that are also enveloped. The understanding of these processes will help us to understand how HBV replicates and causes diseases, which will help to improve the treatments for HBV patients.

Viroid-like colonists of human microbiomes.

Here, we describe "obelisks," a class of heritable RNA elements sharing several properties: (1) apparently circular RNA ∼1 kb genome assemblies, (2) predicted rod-like genome-wide secondary structures, and (3) open reading frames encoding a novel "Oblin" protein superfamily. A subset of obelisks includes a variant hammerhead self-cleaving ribozyme. Obelisks form their own phylogenetic group without detectable similarity to known biological agents. Surveying globally, we identified 29,959 distinct obelisks (clustered at 90% sequence identity) from diverse ecological niches. Obelisks are prevalent in human microbiomes, with detection in ∼7% (29/440) and ∼50% (17/32) of queried stool and oral metatranscriptomes, respectively. We establish Streptococcus sanguinis as a cellular host of a specific obelisk and find that this obelisk's maintenance is not essential for bacterial growth. Our observations identify obelisks as a class of diverse RNAs of yet-to-be-determined impact that have colonized and gone unnoticed in human and global microbiomes.

Perspectives of People Living With Chronic Hepatitis D: Impact of Disease and Unmet Needs Along the Care Cascade.

Hepatitis D virus leads to a severe form of viral hepatitis and affects nearly 5% of people living with chronic hepatitis B. Chronic infection with hepatitis D virus leads to more rapid progression to cirrhosis, hepatocellular carcinoma and ultimately liver disease-related death compared with hepatitis B monoinfection. Health outcomes and treatment adherence can be affected by patient perception of, engagement in, and satisfaction with care. Our objective was to better understand the experiences of people with chronic hepatitis D, identify their preferred sources of information, and recognise unmet needs from their perspectives. Sixty-seven participants from the United States and the European Union took part in monthly, online, self-guided surveys for a minimum of 3 months with an optional extension. Participants reported feeling anxious and scared at the time of diagnosis but over time came to accept living with chronic hepatitis D. They voiced a need for access to information from trusted sources, fewer barriers to care, and shorter wait times for provider visits and test results after diagnosis. Participants experienced both physical and psychological strain living with chronic hepatitis D. Although most participants reported the ability to continue their regular activities and employment, some stated such activities were done at a reduced pace. Self-reported overall health appeared to be closely linked with emotional support. Understanding patient perspectives, with concurrent clinician perspectives, is crucial when working toward developing solutions to fulfil unmet patient needs associated with chronic hepatitis D management and advancing health equity.

Outcomes of a 1-Year Pilot Study Implementing Universal Hepatitis Delta Virus Testing Among Veterans With Chronic Hepatitis B.

Current US guidelines recommend risk-based testing for hepatitis delta virus (HDV) in persons with chronic hepatitis B (CHB). While there is debate as to whether a risk-based or universal testing approach is most effective, limited data exist on universal HDV testing programs in the United States. We performed a 1-year pilot study evaluating the outcomes of a universal HDV testing approach among US veterans with CHB. All consecutive adults with CHB receiving care at hepatology clinics at a single-centre Veterans Affairs Health System from 1 October 2022 to 30 September 2023 were prospectively tested for anti-HDV antibody (anti-HDV). Patients who were anti-HDV Ab-positive were subsequently tested for HDV RNA. Comparison of HDV testing between groups utilised chi-square testing. A total of 91 consecutive CHB patients (90.0% male, mean age 60.9 ± 14.1 years, 73.9% Asian, 26.1% non-Asia, 16.5% cirrhosis and 17.1% with active or past history of drug use) had anti-HDV ordered. Overall, 76.9% (n = 70) completed anti-HDV testing; 4.3% (n = 3) were positive. HDV RNA testing was ordered in all three patients; two patients completed HDV RNA testing and one had detectable HDV RNA. No significant differences in completion of anti-HDV testing was observed by age, sex, race/ethnicity, cirrhosis status or drug use history. Among a single-centre prospective cohort study piloting a universal HDV testing approach, one patient with viremic HDV was identified. Implementing true reflex testing of all CHB patients with anti-HDV, followed by automated HDV RNA testing for anti-HDV-positive patients would improve the HDV testing cascade and timely diagnosis of HDV.

Impact of Hepatitis Delta Virus Infection on the Selection of Hepatitis B Surface Antigen Mutations.

The interaction of multiple viruses in one host is thought to enhance the development of mutations. However, the impact of hepatitis D virus (HDV) positivity on the development of unique hepatitis B virus (HBV) mutations among people living with human immunodeficiency virus (HIV) (PLWH) remains poorly understood in African countries, including Botswana. We used HBV sequences generated from the Botswana Combination Prevention Project (BCPP), which is the largest pair-matched cluster-randomized HIV trial in Botswana. Only participants with available HBV sequences (n = 55) were included in our study ([HIV/HBV-positive (n = 50) and HIV/HBV/HDV-positive (n = 5)]. Geno2pheno was used to determine HBV genotypes, and HBV surface region sequences (all subgenotype A1) were aligned in AliView for mutational analysis, while the impact of mutations was assessed using Phyre2. Our results identified 182 common mutations between the two groups. In the HIV/HBV/HDV cohort, only three mutations (L95W, W156Q, C221Y) were classified as deleterious, with only L95W being the most frequent. In the HIV/HBV cohort, four mutations (W199R, C221A, C221S, W223G) were also classified as deleterious. Our results demonstrate the presence of unique HBV mutations among the HIV/HBV/HDV-positive cohort. Functional characterization of these mutations is recommended to determine their effect on HDV.

High Diagnostic Value of Transient Elastography for Advanced Fibrosis and Cirrhosis in Patients With Chronic Hepatitis Delta.

BACKGROUND & AIMS: Liver biopsy remains the gold standard for fibrosis staging in patients with chronic hepatitis delta (CHD). Here, we comparatively evaluated the performance of transient elastography (TE) and biomarkers for the diagnosis of liver fibrosis in patients with CHD. METHODS: A total of 230 HDV-infected RNA-positive patients from various centers who underwent liver biopsy and liver stiffness measurements (LSMs) using Fibroscan, within a period of 6 months maximum, were investigated retrospectively. Area under the receiver operating characteristic curve and Youden index were used to establish cutoff values of LSM. TE was compared with other noninvasive tests: aspartate aminotransferase to platelet ratio index, Fibrosis-4, and Delta-4 fibrosis scores. RESULTS: Histologic fibrosis stage distribution was: 20.4% for F0-F1; 27.0% for F2; 18.7% for F3; and 33.9% for F4. TE demonstrated good diagnostic performance for detecting cirrhosis and advanced fibrosis with an Area under the receiver operating characteristic curve of 0.88 and 0.86, which were significantly higher than those obtained with the other noninvasive tests (P = .004 and P < .001). With a cutoff value of >12 kPa for cirrhosis, the sensitivity was 70.5%, specificity was 86.2%, positive predictive value was 72.4%, negative predictive value was 85.1%, and accuracy was 80.9%. Using 10.4 kPa as the cutoff value for F3, the sensitivity was 70.2%, specificity was 83.5%, positive predictive value was 82.5%, negative predictive value was 71.7%, and accuracy was 76.5%. In 89% of patients with LSM ≤6.2 kPa, liver biopsy disclosed only absent or minimal fibrosis. CONCLUSION: TE demonstrated good diagnostic performance for advanced fibrosis and cirrhosis in patients with CHD. Advanced fibrosis is highly probable for LSM values ≥10 kPa. LSM values <6 kPa almost totally exclude significant fibrosis. Between 6 and 10 kPa, liver biopsy should be discussed.

vHDvDB 2.0: Database and Group Comparison Server for Hepatitis Delta Virus.

The hepatitis delta virus (HDV) is a unique pathogen with significant global health implications, affecting individuals who are coinfected with the hepatitis B virus (HBV). HDV infection has profound clinical consequences, manifesting either as coinfection with HBV, resulting in acute hepatitis and potential liver failure, or as superinfection in chronic HBV cases, substantially increasing the risk of cirrhosis and hepatocellular carcinoma. Given the complex dynamics of HDV infection and the urgent need for advanced research tools, this article introduces vHDvDB 2.0, a comprehensive HDV full-length sequence database. This innovative platform integrates data preprocessing, secondary structure prediction, and epidemiological research tools. The primary goal of vHDvDB 2.0 is to consolidate HDV sequence data into a user-friendly repository, thereby facilitating access for researchers and enhancing the broader scientific understanding of HDV. The significance of this database lies in its potential to streamline HDV research by providing a centralized resource for analyzing viral sequences and exploring genotype-specific characteristics. It will also enable more in-depth research within the HDV sequence domains.

Effect of Peg-IFN on the viral kinetics of patients with HDV infection treated with bulevirtide.

Background & Aims: Bulevirtide is a first-in-class entry inhibitor antiviral treatment for chronic hepatitis D. The viral kinetics during bulevirtide therapy and the effect of combining bulevirtide with pegylated-interferon (Peg-IFN) are unknown. Methods: We used mathematical modelling to analyze the viral kinetics in two French observational cohorts of 183 patients receiving bulevirtide with or without Peg-IFN for 48 weeks. Results: The efficacy of bulevirtide in blocking cell infection was estimated to 90.3%, whereas Peg-IFN blocked viral production with an efficacy of 92.4%, albeit with large inter-individual variabilities. The addition of Peg-IFN to bulevirtide was associated with a more rapid virological decline, with a rate of virological response (>2 log of decline or undetectability) at week 48 of 86.9% (95% prediction interval [PI] = [79.7-95.0]), compared with 56.1% (95% PI = [46.4-66.7]) with bulevirtide only. The model was also used to predict the probability to achieve a cure of viral infection, with a rate of 8.8% (95% PI = [3.5-13.2]) with bulevirtide compared with 18.8% (95% PI = [11.6-29.0]) with bulevirtide + Peg-IFN. Mathematical modelling suggests that after 144 weeks of treatment, the rates of viral cure could be 42.1% (95% PI = [33.3-52.6]) with bulevirtide and 66.7% (95% PI = [56.5-76.8]) with bulevirtide + Peg-IFN. Conclusions: In this analysis of real-world data, Peg-IFN strongly enhanced the kinetics of viral decline in patients treated with bulevirtide. Randomized clinical trials are warranted to assess the virological and clinical benefit of this combination, and to identify predictors of poor response to treatment. Impact and implications: Bulevirtide has been approved for chronic HDV infection by regulatory agencies in Europe based on its good safety profile and rapid virological response after treatment initiation, but the optimal duration of treatment and the chance to achieve a sustained virological response remain unknown. The results presented in this study have a high impact for clinicians and investigators as they provide important knowledge on the long-term virological benefits of a combination of Peg-IFN and bulevirtide in patients with CHD. Clinical trials are now warranted to confirm those predictions.

Patient-reported outcomes in chronic hepatitis delta: An exploratory analysis of the Phase III MYR301 trial of bulevirtide.

BACKGROUND & AIMS: Once-daily treatment of chronic hepatitis delta (CHD) with bulevirtide is well tolerated and associated with significant reductions in HDV RNA in the blood and in biochemical liver disease activity. This study explored the effects of 48-week bulevirtide treatment on health-related quality of life (HRQoL) in patients with CHD. METHODS: In an open-label, randomised, Phase 3 trial, 150 patients with CHD and compensated liver disease were stratified by liver cirrhosis status and randomised 1:1:1 to no treatment (control), bulevirtide 2 mg/day, or bulevirtide 10 mg/day for 48 weeks. HRQoL was evaluated by the following patient-reported outcome (PRO) instruments at baseline, 24 weeks, and 48 weeks: EQ-5D-3L, Hepatitis Quality of Life Questionnaire (HQLQ), and Fatigue Severity Scale (FSS). RESULTS: Patient characteristics and HRQoL scores were balanced at baseline between the treatment (2 mg, n = 49; 10 mg, n = 50) and control (n = 51) groups. Patients receiving 2-mg bulevirtide reported significant improvements compared with controls on the HQLQ domains of role physical, hepatitis-specific limitations, and hepatitis-specific health distress. Numerically higher scores for general health, hepatitis-specific limitations, and hepatitis-specific health distress domains were reported by patients with cirrhosis who received bulevirtide vs control. FSS scores remained stable across treatment groups throughout. At week 48, patients in the 2-mg group showed greater mean improvement from baseline in health status compared with controls on the EQ-5D-3L visual analogue scale. CONCLUSION: PROs indicate that 48-week treatment with bulevirtide monotherapy may improve aspects of HRQoL in patients with CHD. IMPACT AND IMPLICATIONS: Bulevirtide 2 mg is the only approved treatment for patients with chronic hepatitis delta (CHD) in the EU. Patients with CHD have worse quality of life scores than those with chronic hepatitis B. Bulevirtide treatment for 48 weeks reduced HDV RNA and alanine aminotransferase levels and was well tolerated among patients with CHD. For the first time, this study shows that patients who received bulevirtide therapy for 48 weeks reported improvements in physical and hepatitis-related quality of life domains compared to those who did not receive therapy (control group). CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier, NCT03852719.

Assessment of performance and comparison of three commercial HDV RNA detection assays: implications for diagnosis and treatment monitoring.

Objectives: Precise HDV-RNA detection and quantification are pivotal for diagnosis and monitoring of response to newly approved treatment. We evaluate the performance of three HDV RNA detection and quantification assays. Methods: Hepatitis Delta RT-PCR system kit, EurobioPlex HDV assay, and RoboGene HDV RNA Quantification kit 2.0 were used for testing 151 HBsAg-positive samples, 90 HDV-RNA negative and 61 HDV-RNA positive. We also evaluated serial dilutions of the WHO international standard for HDV, PEI 7657/12. All HDV-RNA positive samples were genotyped using a next-generation sequencing strategy. Results: Qualitative results indicated a 100% concordance between tests. Quantitative results correlated well, r2 = 0.703 (Vircell-vs-Eurobio), r2 = 0.833 (Vircell-vs-RoboGene), r2 = 0.835 (Robogene-vs-Eurobio). Bias index was 2.083 (Vircell-vs-Eurobio), -1.283 (Vircell-vs-RoboGene), and -3.36 (Robogene-vs-Eurobio). Using the WHO IS, Vircell overestimated the viral load by 0.98 log IU/mL, Eurobio by 1.46 log IU/mL, and RoboGene underestimated it by 0.98 log IU/mL. Fifty-nine samples were successfully genotyped (Genotype 1, n=52; Genotype 5, n=7; Genotype 6, n=1), with similar results for correlation and bias. Conclusion: This study underscores the necessity of using reliable HDV-RNA detection and quantification assays, as evidenced by the high concordance rates in qualitative detection and the observed variability in quantitative results. These findings highlight the importance of consistent assay use in clinical practice to ensure accurate diagnosis and effective treatment monitoring of HDV infection.

Efficacy of Pegylated Interferon-alpha-2a in Chronic Hepatitis Delta: Experience from a Tertiary Care Hospital in Karachi.

Background: Chronic hepatitis D (CHD) along with chronic hepatitis B (CHB) is an important cause of morbidity and mortality in patients with cirrhosis. It is a potentially curable infection that has long awaited a good treatment option. Objective: To ascertain the efficacy of pegylated interferon (PEG-IFN)-alpha-2a in patients suffering from CHD. A tertiary care hospital experience from Pakistan. Materials and methods: The study included 207 CHD polymerase chain reaction (PCR)-positive patients treated with PEG-IFN-alpha-2a between July 2020 and October 2022. Virological response rate (PCR negative) at weeks 24 and 48 was the primary endpoint. Secondary outcomes included partial response (>2 log reduction in PCR) and treatment failure rate (<2 log reduction in PCR). Results: A total of 187 patients started PEG-IFN therapy, and 148 patients completed the assigned 48 weeks of therapy. Patients' mean age was 25.7 years with 65% being males. The virological response rate was 40.5% at week 24 and 32.4% at week 48. The partial response rate was 24% at both weeks 24 and 48. The treatment failure rate was 36% at week 24 and 44% at week 48. Hemoglobin, white blood cell (WBC) count, and total bilirubin were found to be predictive of treatment response. Side effects led to treatment discontinuation among eighteen patients and one patient died due to hepatic failure. Conclusion: Therapy with PEG-IFN-alpha-2a shows suboptimal outcomes in patients with CHD. There is a strong need for more effective alternate therapies for CHD patients. How to cite this article: Butt N, Usmani MT, Hussain R, et al. Efficacy of Pegylated Interferon-alpha-2a in Chronic Hepatitis Delta: Experience from a Tertiary Care Hospital in Karachi. Euroasian J Hepato-Gastroenterol 2024;14(1):51-55.

Investigating the Genetic Diversity of Hepatitis Delta Virus in Hepatocellular Carcinoma (HCC): Impact on Viral Evolution and Oncogenesis in HCC.

Hepatitis delta virus (HDV), an RNA virus with two forms of the delta antigen (HDAg), relies on hepatitis B virus (HBV) for envelope proteins essential for hepatocyte entry. Hepatocellular carcinoma (HCC) ranks third in global cancer deaths, yet HDV's involvement remains uncertain. Among 300 HBV-associated HCC serum samples from Taiwan's National Health Research Institutes, 2.7% (8/300) tested anti-HDV positive, with 62.7% (5/8) of these also HDV RNA positive. Genotyping revealed HDV-2 in one sample, HDV-4 in two, and two samples showed mixed HDV-2/HDV-4 infection with RNA recombination. A mixed-genotype infection revealed novel mutations at the polyadenylation signal, coinciding with the ochre termination codon for the L-HDAg. To delve deeper into the possible oncogenic properties of HDV-2, the predominant genotype in Taiwan, which was previously thought to be less associated with severe disease outcomes, an HDV-2 cDNA clone was isolated from HCC for study. It demonstrated a replication level reaching up to 74% of that observed for a widely used HDV-1 strain in transfected cultured cells. Surprisingly, both forms of HDV-2 HDAg promoted cell migration and invasion, affecting the rearrangement of actin cytoskeleton and the expression of epithelial-mesenchymal transition markers. In summary, this study underscores the prevalence of HDV-2, HDV-4, and their mixed infections in HCC, highlighting the genetic diversity in HCC as well as the potential role of both forms of the HDAg in HCC oncogenesis.

Exosomes as Conduits: Facilitating Hepatitis B Virus-Independent Hepatitis D Virus Transmission and Propagation in Hepatocytes.

A number of research studies, including ours, have spotlighted exosomes as critical facilitators of viral dissemination. While hepatitis B virus (HBV) transmission through exosomes has been studied, the focus on its satellite virus, the hepatitis delta virus (HDV), has been unexplored in this context. HDV, although being a defective virus, can replicate its genome autonomously within hepatocytes, independently of HBV. Investigations on Huh7 cells revealed an intriguing phenomenon: the HDV proteins, S-HDAg and L-HDAg, are transmitted between cells without a complete viral structure. Detailed analysis further revealed that the expression of these proteins not only bolstered exosome secretion but also ensured their enrichment within these vesicles. Our experimental approach utilized transfection of various plasmids to examine the role of HDV RNA and proteins in the process. One salient finding was the differential propagation of the HDV proteins S-HDAg and L-HDAg, suggesting intricate molecular mechanisms behind their transmission. Notably, the purity of our exosome preparations was monitored using markers such as TSG101 and CD81. Importantly, these exosomes were found to carry both HDV RNA and proteins, highlighting their role in HDV dissemination. This novel study underscores the role of exosomes in mediating the transmission of HDV components between hepatocytes independent of HBV. These revelations about the exosomal pathway of HDV transmission provide a foundation for the development of innovative therapeutic strategies against HDV infections.

Analysis of Replication, Cell Division-Mediated Spread, and HBV Envelope Protein-Dependent Pseudotyping of Three Mammalian Delta-like Agents.

The human hepatitis delta virus (HDV) is a satellite RNA virus that depends on hepatitis B virus (HBV) surface proteins (HBsAg) to assemble into infectious virions targeting the same organ (liver) as HBV. Until recently, the evolutionary origin of HDV remained largely unknown. The application of bioinformatics on whole sequence databases lead to discoveries of HDV-like agents (DLA) and shed light on HDV's evolution, expanding our understanding of HDV biology. DLA were identified in heterogeneous groups of vertebrates and invertebrates, highlighting that the evolution of HDV, represented by eight distinct genotypes, is broader and more complex than previously foreseen. In this study, we focused on the characterization of three mammalian DLA discovered in woodchuck (Marmota monax), white-tailed deer (Odocoileus virginianus), and lesser dog-like bat (Peropteryx macrotis) in terms of replication, cell-type permissiveness, and spreading pathways. We generated replication-competent constructs expressing 1.1-fold over-length antigenomic RNA of each DLA. Replication was initiated by transfecting the cDNAs into human (HuH7, HeLa, HEK293T, A549) and non-human (Vero E6, CHO, PaKi, LMH) cell lines. Upon transfection and replication establishment, none of the DLA expressed a large delta antigen. A cell division-mediated viral amplification assay demonstrated the capability of non-human DLA to replicate and propagate in hepatic and non-hepatic tissues, without the requirement of envelope proteins from a helper virus. Remarkably L-HDAg but not S-HDAg from HDV can artificially mediate envelopment of WoDV and DeDV ribonucleoproteins (RNPs) by HBsAg to form infectious particles, as demonstrated by co-transfection of HuH7 cells with the respective DLA expression constructs and a plasmid encoding HBV envelope proteins. These chimeric viruses are sensitive to HDV entry inhibitors and allow synchronized infections for comparative replication studies. Our results provide a more detailed understanding of the molecular biology, evolution, and virus-host interaction of this unique group of animal viroid-like agents in relation to HDV.

Hepatocyte Intrinsic Innate Antiviral Immunity against Hepatitis Delta Virus Infection: The Voices of Bona Fide Human Hepatocytes.

The pathogenesis of viral infection is attributed to two folds: intrinsic cell death pathway activation due to the viral cytopathic effect, and immune-mediated extrinsic cellular injuries. The immune system, encompassing both innate and adaptive immunity, therefore acts as a double-edged sword in viral infection. Insufficient potency permits pathogens to establish lifelong persistent infection and its consequences, while excessive activation leads to organ damage beyond its mission to control viral pathogens. The innate immune response serves as the front line of defense against viral infection, which is triggered through the recognition of viral products, referred to as pathogen-associated molecular patterns (PAMPs), by host cell pattern recognition receptors (PRRs). The PRRs-PAMPs interaction results in the induction of interferon-stimulated genes (ISGs) in infected cells, as well as the secretion of interferons (IFNs), to establish a tissue-wide antiviral state in an autocrine and paracrine manner. Cumulative evidence suggests significant variability in the expression patterns of PRRs, the induction potency of ISGs and IFNs, and the IFN response across different cell types and species. Hence, in our understanding of viral hepatitis pathogenesis, insights gained through hepatoma cell lines or murine-based experimental systems are uncertain in precisely recapitulating the innate antiviral response of genuine human hepatocytes. Accordingly, this review article aims to extract and summarize evidence made possible with bona fide human hepatocytes-based study tools, along with their clinical relevance and implications, as well as to identify the remaining gaps in knowledge for future investigations.

Development of a dual channel detection system for pan-genotypic simultaneous quantification of hepatitis B and delta viruses.

Hepatitis B virus (HBV) infection remains a major public health problem and, in associated co-infection with hepatitis delta virus (HDV), causes the most severe viral hepatitis and accelerated liver disease progression. As a defective satellite RNA virus, HDV can only propagate in the presence of HBV infection, which makes HBV DNA and HDV RNA the standard biomarkers for monitoring the virological response upon antiviral therapy, in co-infected patients. Although assays have been described to quantify these viral nucleic acids in circulation independently, a method for monitoring both viruses simultaneously is not available, thus hampering characterization of their complex dynamic interactions. Here, we describe the development of a dual fluorescence channel detection system for pan-genotypic, simultaneous quantification of HBV DNA and HDV RNA through a one-step quantitative PCR. The sensitivity for both HBV and HDV is about 10 copies per microliter without significant interference between these two detection targets. This assay provides reliable detection for HBV and HDV basic research in vitro and in human liver chimeric mice. Preclinical validation of this system on serum samples from patients on or off antiviral therapy also illustrates a promising application that is rapid and cost-effective in monitoring HBV and HDV viral loads simultaneously.

Hepatitis Delta Virus Reporting Requirements in the United States and Territories: A Systematic Review.

Hepatitis D virus (HDV) is a rare coinfection with hepatitis B virus. Currently, HDV is not a nationally notifiable disease in the United States. Only 55% of states and territories require HDV reporting, and most lack defined case definitions. Standardization of reporting requirements is crucial for monitoring HDV epidemiology.

Growing Awareness: Limited Testing and Screening Bias for Hepatitis Delta Virus in Utah 2000-2021.

BACKGROUND: This study assessed the epidemiology of hepatitis delta virus (HDV) within the University of Utah UHealth health care system (2000-2021). METHODS: Analysis of HDV/HBV testing, diagnostic codes, liver enzymes, and comorbidities was performed. RESULTS: Among the 1962 HBV patients, only 22.2% underwent HDV testing, revealing an 8.3% positivity rate for HDV coinfections. This study observed a consistent increase in HBV and HDV cases, with higher HDV detection rates linked to increased testing. Limited HDV testing and potential screening biases were evident. DISCUSSION: Improved HDV testing and surveillance are crucial for early detection and implementation of targeted therapies.

Epidemiology of Viral Hepatitis in the Indigenous Populations of the Arctic Zone of the Republic of Sakha (Yakutia).

The indigenous populations of the Arctic regions of Russia experience the lowest coverage of health-related services. We assessed the prevalence of hepatitis A, B, C, D and E viruses (HAV, HBV, HCV, HDV and HEV) among 367 healthy adult Native people of the Arctic zone of Yakutia. The HAV seroprevalence was above and increased with age. The anti-HEV IgM and IgG antibody detection rates were 4.1% and 2.5%, respectively. The average HBsAg detection rate was 4.6%, with no positive cases identified in participants aged under 30 years, confirming the effectiveness of the newborn vaccination program that began in 1998. Anti-HDV antibodies were detected in 29.4% of HBsAg-positive cases. The anti-HCV and HCV RNA detection rates peaked in the age cohort of 50-59 years (10.8% and 3.9%). No statistically significant gender differences in the prevalence of different viral hepatitis were observed. The time-scaled phylogenetic analysis demonstrated that all HBV genotype A and D strains isolated in this study were autochthonous and had an estimated most common recent ancestor (MCRA) age of around the 11th to 14th century. Unlike HBV, the HCV strains of subtypes 1b, 2a and 2k/1b were introduced from other regions of Russia in the 1980s and 1990s. The HCV 1b sequence analysis revealed a series of transmission events. In conclusion, these data emphasize the urgent need for expanded viral hepatitis screening and care programs in the indigenous populations of the Arctic zone of Yakutia.