A historical perspective on the discovery and elucidation of the hepatitis B virus

Discovery of Hepatitis E and Its Impact on Global Health: A Journey of 44 Years about an Incredible Human-Interest Story

The story of the discovery of hepatitis E originated in the late 1970s with my extreme belief that there was a hidden saga in the relationship between jaundice and pregnancy in developing countries and the opportunity for a massive epidemic of viral hepatitis, which hit the Gulmarg Kashmir region in November 1978. Based on data collected from a door-to-door survey, the existence of a new disease, epidemic non-A, non-B hepatitis, caused by a hitherto unknown hepatitis virus, was announced. This news was received by the world community with hype and skepticism. In the early 1980s, the world watched in awe as an extreme example of human self-experimentation led to the identification of VLP. In 1990, a cDNA clone from the virus responsible for epidemic non-A, non-B hepatitis was isolated. Over the years, we traversed three eras of ambiguity, hope, and hype of hepatitis E research and conducted several seminal studies to understand the biology of HEV and manifestations of hepatitis E. Many milestones have been reached on the long and winding road of hepatitis E research to understand the structure, biology, and diversity of the agent, changing the behavior of the pathogen in developed countries, and the discovery of a highly effective vaccine.

[Hepatitis B vaccines-history, achievements, challenges, and perspectives]

Die ersten Impfversuche gegen das Hepatitis-B-Virus (HBV) erfolgten 1970, noch bevor die Natur des dafür verwendeten „Australia-Antigens“ bekannt war. Bald darauf wurde dieses Antigen als Hüllprotein des HBV erkannt (HBV Surface Antigen, HBsAg), dann aus HBV-haltigem Plasma gereinigt und später gentechnisch in Hefezellen hergestellt. Die hohe Wirksamkeit des HBsAg-Impfstoffs wurde vielfach bewiesen, insbesondere bei Neugeborenen von HBV-infizierten Müttern, die sonst fast immer chronische HBV-Träger werden. Auch bei älteren Kindern und Erwachsenen schützt die Impfung und wird seit 1984 weltweit angewendet, was zu einer ungefähr 10-fachen Abnahme der HBV-Infektionen bei den Geimpften geführt hat.

Es gibt dennoch verschiedene Herausforderungen bei der Hepatitis-B-Impfung. Bei Neugeborenen von hochvirämischen Müttern kann die Impfung versagen. Bei verringerter Immunkompetenz kann die Bildung schützender Antikörper ausbleiben, aber auch bei Risikofaktoren wie höherem Alter, Rauchen oder Übergewicht. Frühe Impfstudien belegten, dass Impfstoffe mit dem HBsAg-Subtyp adw2 auch gegen HBV mit anderen HBsAg-Subtypen schützen, neuere Beobachtungen zeigen aber, dass die Schutzwirkung gegen heterologe Subtypen schwächer ist. Gelegentlich werden auch Escape-Mutationen beobachtet.

Die meisten jetzigen Impfstoffe beruhen auf dem Kenntnisstand vor 40 Jahren und könnten wesentlich verbessert werden. Eine Einbeziehung der bislang fehlenden PräS-Domänen der HBV-Hülle in die Impfstoffe würde die wichtigsten schützenden T‑ und B‑Zellepitope einbringen. Die Expression in Säugerzellkulturen verbessert die native Faltung der neutralisierenden HBsAg-Epitope und die Verwendung von regional vorherrschenden HBsAg-Subtypen würde die Schutzwirkung erhöhen. Optimale Adjuvanzien oder Epitopträger könnten die Immunogenität auch für eine HBV-Immuntherapie steigern.

Cancer Etiology and Prevention Principle: "1 + X"

Cancer was previously thought to be an inevitable aspect of human health with no effective treatments. However, the results of in-depth cancer research suggest that most types of cancer may be preventable. Therefore, a comprehensive understanding of the disparities in cancer burden caused by different risk factors is essential to inform and improve cancer prevention and control. Here, we propose the cancer etiology and prevention principle "1 + X," where 1 denotes the primary risk factor for a cancer and X represents the secondary contributing risk factors for the cancer. We elaborate upon the "1 + X" principle with respect to risk factors for several different cancer types. The "1 + X" principle can be used for precise prevention of cancer by eliminating the main cause of a cancer and minimizing the contributing factors at the same time.

Hepatitis B Virus DNA Integration, Chronic Infections and Hepatocellular Carcinoma

Hepatitis B Virus (HBV) is an Old World virus with a high mutation rate, which puts its origins in Africa alongside the origins of Homo sapiens, and is a member of the Hepadnaviridae family that is characterized by a unique viral replication cycle. It targets human hepatocytes and can lead to chronic HBV infection either after acute infection via horizontal transmission usually during infancy or childhood or via maternal-fetal transmission. HBV has been found in ~85% of HBV-related Hepatocellular Carcinomas (HCC), and it can integrate the whole or part of its genome into the host genomic DNA. The molecular mechanisms involved in the HBV DNA integration is not yet clear; thus, multiple models have been described with respect to either the relaxed-circular DNA (rcDNA) or the double-stranded linear DNA (dslDNA) of HBV. Various genes have been found to be affected by HBV DNA integration, including cell-proliferation-related genes, oncogenes and long non-coding RNA genes (lincRNAs). The present review summarizes the advances in the research of HBV DNA integration, focusing on the evolutionary and molecular side of the integration events along with the arising clinical aspects in the light of WHO's commitment to eliminate HBV and viral hepatitis by 2030.

Viral hepatitis: Milestones, unresolved issues, and future goals

In this review the current overall knowledge on hepatitis A, B, C, D, and E will be discussed. These diseases are all characterized by liver inflammation but have significant differences in distribution, transmission routes, and outcomes. Hepatitis B virus and hepatitis C virus are transmitted by exposure to infected blood, and in addition to acute infection, they can cause chronic hepatitis, which in turn can evolve into cirrhosis. It is estimated that more than 300 million people suffer from chronic hepatitis B or C worldwide. Hepatitis D virus, which is also transmitted by blood, only affects hepatitis B virus infected people, and this dual infection results in worse liver-related outcomes. Hepatitis A and E spread via the fecal-oral route, which corresponds mainly to the ingestion of food or water contaminated with infected stools. However, in developed countries hepatitis E is predominantly a zoonosis. Although hepatitis A virus and hepatitis E virus are usually responsible for a self-limiting hepatitis, a serious, rarely fatal illness is also possible, and in immunosuppressed patients, such as organ transplant recipients, hepatitis E virus infection can become chronic. The description of goals achieved, unresolved issues, and the latest research on this topic may make it possible to speculate on future scenarios in the world of viral hepatitis.

Genomics of Viral Hepatitis-Associated Liver Tumors

Virus-related liver carcinogenesis is one of the main contributors of cancer-related death worldwide mainly due to the impact of chronic hepatitis B and C infections. Three mechanisms have been proposed to explain the oncogenic properties of hepatitis B virus (HBV) infection: induction of chronic inflammation and cirrhosis, expression of HBV oncogenic proteins, and insertional mutagenesis into the genome of infected hepatocytes. Hepatitis B insertional mutagenesis modifies the function of cancer driver genes and could promote chromosomal instability. In contrast, hepatitis C virus promotes hepatocellular carcinoma (HCC) occurrence mainly through cirrhosis development whereas the direct oncogenic role of the virus in human remains debated. Finally, adeno associated virus type 2 (AAV2), a defective DNA virus, has been associated with occurrence of HCC harboring insertional mutagenesis of the virus. Since these tumors developed in a non-cirrhotic context and in the absence of a known etiological factor, AAV2 appears to be the direct cause of tumor development in these patients via a mechanism of insertional mutagenesis altering similar oncogenes and tumor suppressor genes targeted by HBV. A better understanding of virus-related oncogenesis will be helpful to develop new preventive strategies and therapies directed against specific alterations observed in virus-related HCC.

Nobel Prize for the Discovery of Hepatitis B and C: A Brief History in Time

In 2020, the Noble Prize for Medicine jointly went to three scientists for hepatitis C virus-related discoveries. Earlier in 1976, an American scientist won this award for the discovery of hepatitis B virus. The Noble Prize, constituted as per the will of Alfred Noble, is awarded every year for achievements that benefit human beings in the best possible way. Although humans have known hepatitis as a deadly disease for hundreds of years, it was the discovery of hepatitis B and C viruses that changed the way we knew the hepatitis viruses forever and paved the way for saving millions of lives all over the world, the reason why the Noble Committee has on two different occasions picked up the great minds behind the discovery of these two hepatitis viruses and recognized them by conferring them with the highest recognition that one dreams of. How to cite this article: Al-Mahtab M, Roy PP, Khan MSI, et al. Nobel Prize for the Discovery of Hepatitis B and C: A Brief History in Time. Euroasian J Hepatogastroenterol 2020;10(2):98-100.

Diagnostic accuracy of LAMP assay for HBV infection

Background

Detection of hepatitis B virus (HBV) is vital for the diagnosis of hepatitis B infection. A novel test loop‐mediated isothermal amplification (LAMP) has been successfully applied to detect various pathogens. However, the accuracy of LAMP in diagnosing HBV remains unclear. Therefore, in the present study, the accuracy of LAMP for HBV detection was evaluated systematically.

Methods

Embase, Cochrane Library, and PubMed databases were searched for studies using LAMP to detect HBV. Then, two researchers extracted data and assessed the quality of literature using the QUADAS‐2 tool independently. I² statistic and chi‐square test were analyzed to investigate the heterogeneity, and Deek's funnel plot assessed the publication bias. The pooled sensitivity (SEN), specificity (SPE), positive LR (PLR), negative LR (NLR), diagnostic odds ratio (DOR), and 95% confidence intervals were displayed in forest plots. We calculated the area under the curve (AUC) to assess the overall efficiency of LAMP for HBV detection.

Results

A total of nine studies with 1298 samples were finally included in this evaluation. The pooled sensitivity and specificity of HBV detection were 0.91 (95% CI: 0.89 ~ 0.92) and 0.97 (95% CI: 0.94 ~ 0.99), respectively. The PLR, NLR, and DOR were 16.93 (95% CI: 6.15 ~ 46.55), 0.08 (95% CI: 0.05 ~ 0.14), and 397.57 (95% CI: 145.41 ~ 1087.07). Besides, the AUC was 0.9872, and Deek's plot suggested that there existed publication bias in the studies.

Conclusion

Compared with PCR, LAMP is a simple, rapid, and effective assay to diagnose HBV. However, additional evidence is essential to confirm that LAMP can replace other methods in diagnosing HBV infection.

Small size, big impact: how studies of small DNA tumour viruses revolutionized biology

Intense study of three families of small tumour viruses with double-stranded DNA genomes, carried out over 50 years, has had a profound impact on biology. The polyomaviruses and papillomaviruses have circular DNA genomes of approximately 5000 and approximately 8000 base-pairs, respectively, and thus encode only a handful of proteins. Adenoviruses have a 32 000-base-pair linear DNA genome, still far smaller than the three billion-base-pair human genome. Members of all three virus families can transform cultured cells to tumorigenicity and cause tumours in experimental animals. Several human papillomaviruses (HPV) and at least one polyomavirus are oncogenic in humans. Early analysis of these viruses, particularly the polyomavirus SV40, led to the development of many powerful experimental tools, including restriction mapping, site-directed mutagenesis, gene transfer, genome-wide sequencing and recombinant DNA. These tools have since been refined and used to study cellular genes, revolutionizing our understanding of biology. These tools were also applied to the viruses themselves. Analysis of the virus life cycle and the effect of these viruses on cells yielded important new insights into many aspects of gene expression, DNA replication, cell biology and carcinogenesis. These studies have also led to vaccination strategies to prevent infection and cancer in humans. This article is part of the theme issue 'Silent cancer agents: multi-disciplinary modelling of human DNA oncoviruses'.

Assessment of Knowledge, Attitude and Vaccination Status of Hepatitis B among Nursing Training Students in Ho, Ghana

BACKGROUND

Viral hepatitis B is a disease condition of the liver caused by the hepatitis B virus, and it leads to complications such as cancer and cirrhosis. This poses an occupational hazard because about 66,000 health care workers get infected with the virus annually. Adequate knowledge and right attitude of health workers are required to prevent the disease. Compared to average health care workers, trainee nurses are more vulnerable to the disease due to inadequate knowledge on infection control guidelines.

PURPOSE OF THE STUDY

The study assessed the knowledge, attitude and vaccination status of hepatitis B among nursing training students in Ho, Ghana.

METHOD

A descriptive cross-sectional study was carried out between September and December 2017 in which 358 student nurses were randomly selected to participate in this study. A self-administered structured questionnaire was used as a data collection tool to get information from the students. Data were then entered into SPSS version 20 for cleaning and analysis.

RESULT

The majority of participants were between the ages of 20-26 years with the mean age 21.56 (SD ± 2.65). About 78.2% knew the disease is caused by a virus. Also, 69.8% reported transmission through needle stick injuries, and the mean knowledge score was 29.6 (SD ± 6.98). Also, 68.8% recapped needles (P = 0.012), and 49.4% have taken the full three doses of vaccines.

CONCLUSION

The study points to a satisfactory knowledge and vaccination status of hepatitis B among the trainee nurses but poor attitude toward the disease, hence the need for massive health education among the nurses.

Research priorities for the discovery of a cure for chronic hepatitis B: Report of a workshop

In early 2017, the Hepatitis B Foundation invited 30 experts in the fields of hepatitis B and liver cancer research to identify projects they deemed important to the goal of finding a cure for chronic hepatitis B and D and the diseases with which these viral infections are associated. They were also asked to identify general categories of research and to prioritize sub-project topics within those areas. The experts generally agreed on broadly defined areas of research, but there was usually little difference between the highest and lowest scoring projects; for the most part, all programs described in this document were considered valuable and necessary. An executive summary of this discussion was recently published (Alter et al., Hepatology 2017). The present manuscript reports the areas of research identified by the workshop participants, provides a brief rationale for their selection, and attempts to express differences among the priorities assigned to each area of research, when such distinctions were expressed.