Hepatitis D | |
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Other names | Hepatitis delta |
Specialty | Gastroenterology, infectious disease |
Symptoms | Feeling tired, nausea and vomiting [1] |
Complications | Cirrhosis [1] |
Causes | Hepatitis D virus [1] |
Diagnostic method | Immunoglobulin G [2] |
Treatment | Antivirals, pegylated interferon alpha [2] |
Medication | Bulevirtide |
Hepatitis D is a type of viral hepatitis [3] caused by the hepatitis delta virus (HDV). [4] [5] HDV is one of five known hepatitis viruses: A, B, C, D, and E. HDV is considered to be a satellite (a type of subviral agent) because it can propagate only in the presence of the hepatitis B virus (HBV). [6] Transmission of HDV can occur either via simultaneous infection with HBV (coinfection) or superimposed on chronic hepatitis B or hepatitis B carrier state (superinfection).
HDV infecting a person with chronic hepatitis B (superinfection) is considered the most serious type of viral hepatitis due to its severity of complications. [7] These complications include a greater likelihood of experiencing liver failure in acute infections and a rapid progression to liver cirrhosis, with an increased risk of developing liver cancer in chronic infections. [8] In combination with hepatitis B virus, hepatitis D has the highest fatality rate of all the hepatitis infections, at 20%. A recent estimate from 2020 suggests that currently 48 million people are infected with this virus. [9]
Hepatitis D | |
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Synonym | Delta hepatitis |
Type of Virus | ssRNA |
Incubation Period | 2–12 weeks |
Transmission | Parenteral |
Carrier State | Yes |
Immunity Passive immunization Active immunization | Hyperimmune globulin Vaccine (hepatitis B) |
Hepatitis delta virus | |
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Schematic representation of the Hepatitis delta virus virion | |
Virus classification | |
(unranked): | Virus |
Realm: | Ribozyviria |
Family: | Kolmioviridae |
Genus: | Deltavirus |
Species [10] | |
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The hepatitis delta viruses, or HDV, are eight species of negative-sense single-stranded RNA viruses (or virus-like particles) classified together as the genus Deltavirus, within the realm Ribozyviria . [11] The HDV virion is a small, spherical, enveloped particle with a 36 nm diameter; its viral envelope contains host phospholipids, as well as three proteins taken from the hepatitis B virus—the large, medium, and small hepatitis B surface antigens. This assembly surrounds an inner ribonucleoprotein (RNP) particle, which contains the genome surrounded by about 200 molecules of hepatitis D antigen (HDAg) for each genome. The central region of HDAg has been shown to bind RNA. [12] Several interactions are also mediated by a coiled-coil region at the N terminus of HDAg. [13] [14]
The HDV genome is negative sense, single-stranded, closed circular RNA; with a genome of approximately 1700 nucleotides, HDV is the smallest "virus" known to infect animals. It has been proposed that HDV may have originated from a class of plant pathogens called viroids, which are much smaller than viruses. [15] [16] Its genome is unique among animal viruses because of its high GC nucleotide content. Its nucleotide sequence is about 70% self-complementary, allowing the genome to form a partially double-stranded, rod-like RNA structure. [17] HDV strains are highly divergent; fusions of different strains exist and sequences had been deposited in public databases employing different start sites for the circular viral RNA involved. This had resulted in something of chaos with respect to molecular classification of this virus, a situation which has been resolved recently with the adoption of a proposed reference genome and a uniform classification system. [18]
Like hepatitis B, HDV gains entry into liver cells via the sodium taurocholate cotransporting polypeptide (NTCP) [19] bile transporter. HDV recognizes its receptor via the N-terminal domain of the large hepatitis B surface antigen, HBsAg. [20] Mapping by mutagenesis of this domain has shown that amino acid residues 9–15 make up the receptor-binding site. [21] After entering the hepatocyte, the virus is uncoated and the nucleocapsid translocated to the nucleus due to a signal in HDAg [22] Since the HDV genome does not code for an RNA polymerase to replicate the virus' genome, the virus makes use of the host cellular RNA polymerases. Initially thought to use just RNA polymerase II, [23] [24] now RNA polymerases I and III have also been shown to be involved in HDV replication. [25] Normally RNA polymerase II utilizes DNA as a template and produces mRNA. Consequently, if HDV indeed utilizes RNA polymerase II during replication, it would be the only known animal pathogen capable of using a DNA-dependent polymerase as an RNA-dependent polymerase.[ citation needed ]
The RNA polymerases treat the RNA genome as double-stranded DNA due to the folded rod-like structure it is in. Three forms of RNA are made; circular genomic RNA, circular complementary antigenomic RNA, and a linear polyadenylated antigenomic RNA, which is the mRNA containing the open reading frame for the HDAg. Synthesis of antigenomic RNA occurs in the nucleolus, mediated by RNA polymerase I, whereas synthesis of genomic RNA takes place in the nucleoplasm, mediated by RNA polymerase II. [26] HDV RNA is synthesized first as linear RNA that contains many copies of the genome. The genomic and antigenomic RNA contain a sequence of 85 nucleotides, the hepatitis delta virus ribozyme, that acts as a ribozyme, which self-cleaves the linear RNA into monomers. These monomers are then ligated to form circular RNA. [27] [28]
Hepatitis delta virus delta antigen | |||||||||
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Identifiers | |||||||||
Symbol | HDV_ag | ||||||||
Pfam | PF01517 | ||||||||
InterPro | IPR002506 | ||||||||
SCOP2 | 1a92 / SCOPe / SUPFAM | ||||||||
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A significant difference between viroids and HDV is that, while viroids produce no proteins, HDV is known to produce one protein, namely HDAg. It comes in two forms; a 27kDa large-HDAg, and a small-HDAg of 24kDa. The N-terminals of the two forms are identical, they differ by 19 more amino acids in the C-terminal of the large HDAg. [29] Both isoforms are produced from the same reading frame which contains an UAG stop codon at codon 196, which normally produces only the small-HDAg. However, editing by cellular enzyme adenosine deaminase acting on RNA (ADAR) changes the stop codon to UGG, allowing the large-HDAg to be produced. [29] [30] Despite having 90% identical sequences, these two proteins play diverging roles during the course of an infection. HDAg-S is produced in the early stages of an infection and enters the nucleus and supports viral replication. HDAg-L, in contrast, is produced during the later stages of an infection, acts as an inhibitor of viral replication, and is required for assembly of viral particles. [31] [32] [33] Thus RNA editing by the cellular enzymes is critical to the virus' life cycle because it regulates the balance between viral replication and virion assembly.[ citation needed ]
The HDV envelope protein has three of the HBV surface proteins anchored to it. The S region of the genome is most commonly expressed and its main function is to assemble subviral particles. HDV antigen proteins combine with the viral genome to form a ribonucleoprotein (RNP) which when enveloped with the subviral particles can form viral-like particles that are almost identical to mature HDV, but they are not infectious. Researchers had concluded that the determinant of infectivity of HDV was within the N-terminal pre-S1 domain of the large protein (L). It was found to be a mediator in binding to the cellular receptor. Researchers Georges Abou Jaoudé and Camille Sureau published an article in 2005 that studied the role of the antigenic loop, found in HDV envelope proteins, in the infectivity of the virus. The antigenic loop, like the N-terminal pre-S1 domain of the large protein, is exposed at the virion surface. Jaoudé and Sureau's study provided evidence that the antigenic loop may be an important factor in HDV entry into the host cell and by mutating parts of the antigenic loop, the infectivity of HDV may be minimized. [34]
The routes of transmission of hepatitis D are similar to those for hepatitis B. Infection is largely restricted to persons at high risk of hepatitis B infection, particularly injecting drug users and persons receiving clotting factor concentrates. Worldwide more than 15 million people are co-infected. HDV is rare in most developed countries, and is mostly associated with intravenous drug use. However, HDV is much more common in the immediate Mediterranean region, sub-Saharan Africa, the Middle East, and the northern part of South America. [35] In all, about 20 million people may be infected with HDV. [36]
As previously stated, patients previously diagnosed with hepatitis B are at risk for hepatitis D infection. Hepatitis D infection risk increases if a person uses injecting drugs, is a hemophiliac, if they are a hemodialysis patient, or through sexual contact with other infected persons.
Vaccination against hepatitis B protects against hepatitis D viral infection as hepatitis D requires hepatitis B viral infection to be present in order to infect and replicate in people. [37] [38] Universal vaccination against hepatitis B virus is recommended by the World Health Organization. The hepatitis B vaccine is routinely given soon after birth (usually within 24 hours) to protect against hepatitis B and D viral infection. [39]
Latex or polyurethane condoms have been shown to prevent the transmission of hepatitis B, and most likely hepatitis D viral infection. [40]
Women who are pregnant or trying to become pregnant should undergo testing for HBV to know if they carry the virus, this will allow prevention strategies to be implemented during the birth of the child. The CDC recommends that all women who are pregnant be tested for hepatitis B viral infection and that all infants of women with HBV infection be given hepatitis B immune globulin (HBIG) and the hepatitis B vaccine within 12 hours of birth to prevent transmission of the virus from mother to child. [41]
Those who get tattoos or body piercings should do so using sterile equipment to prevent the transmission of hepatitis B and D via infected bodily fluids. Hepatitis B and D can also be transmitted from contaminated needles, so those who inject drugs should seek help to stop drug use or use sterile needles and avoid sharing needles with others. [40] Those with hepatitis B or D should also not share razors or other personal care items which may have been contaminated by potentially infectious bodily fluids. [40]
Screening for hepatits D requires testing for anti-HDV antibodies, which indicate past exposure to the virus or current infection. If anti-HDV antibodies are present, then active HDV infection is confirmed by measuring hepatitis D RNA levels. [42] Testing for HDV is only indicated in those who are hepatitis B surface antigen positive (those who have had previous or active infection with hepatitis B) as HDV requires hepatitis B viral infection to infect people. [42] Non-invasive measures of liver fibrosis, such as the biomarker based FibroTest or non-invasive liver imaging such as transient elastography(also known as the FibroScan) have not been validated as quantitative measures of liver fibrosis in those with chronic hepatitis D infection. In those with whom liver fibrosis or cirrhosis is suspected, a liver biopsy is usually needed. [42]
Current established treatments for chronic hepatitis D include conventional or pegylated interferon alpha therapy. [43] Evidence suggests that pegylated interferon alpha is effective in reducing the viral load and the effect of the disease during the time the drug is given, but the benefit generally stops if the drug is discontinued. [44] The efficiency of this treatment does not usually exceed about 20%, and late relapse after therapy has been reported. [45] [46]
In May 2020, the Committee for Medicinal Products for Human Use of the European Medicines Agency approved the antiviral Hepcludex (bulevirtide) to treat hepatitis D. [47] Bulevirtide binds and inactivates the sodium/bile acid cotransporter, blocking hepatitis D virus (as well as hepatitis B virus) from entering hepatocytes. [48] [49] Bulevirtide may be given with pegylated interferon alpha as the two are thought to have a synergistic effect, leading to greater treatment response rates. [42] [50]
In patients with HDV-related compensated Cirrhosis and clinically significant portal hypertension, the treatment with (bulevirtide) was safe, well tolerated and has led to a significant improvement in biochemical variables and an increase in liver function parameters. [51]
Other treatments for hepatitis D which are currently under development include pegylated interferon lambda (λ), which binds to receptors on the hepatocyte surface leading to an intracellular signaling cascade via the JAK-STAT signaling pathway and activation of anti-viral cell mediated immunity. [52] The prenylation inhibitor lonafarnib prevents hepatitis D viral particle assembly by inhibiting the farnesylation of the L-HDAg. [53] REP2139-Ca is a nucleic acid polymer that prevents the release of hepatitis B surface antigen (which is required for assembly of hepatitis D viral particles). [54]
Superinfections, in which hepatitis D viral infection occurs in someone who has chronic hepatitis B (as opposed to co-infection, in which a person is infected with hepatitis B and D simultaneously), are more likely to progress to chronic hepatitis D and are associated with a worse prognosis. [42] 90% of cases of chronic hepatitis D infection are thought to be due to superinfection in those already with hepatitis B. [42] Hepatitis B and D co-infection is likely to lead to acute hepatitis, but is usually self limited with regards to the hepatitis D infection. [42] Chronic hepatitis B and D is associated with a worse prognosis than chronic hepatitis B alone. [42] Infection with both viruses is characterized by a poor prognosis with 75% of those with chronic hepatitis D developing liver cirrhosis within 15 years and a much higher risk of developing liver cancer. [42] Persistent HDV viremia is the most important risk factor for disease progression in those with co-infection or superinfection. [42] Other factors that are responsible for a poor prognosis in chronic hepatitis D include male sex, older age at time of infection, alcohol use, diabetes, obesity and immunodeficiency. [42]
HDV is prevalent worldwide. However, the prevalence is decreasing in many higher income countries due to hepatitis B vaccination programs (although rates remain high in some groups such as those who inject drugs or immigrants from HDV endemic regions). [42] [56] Infection with HDV is a major medical scourge in low income regions of the globe in which HBV prevalence remains high. [56] Currently the Amazon basin and low income regions of Asia and Africa have high rates of HDV, owing to concurrently high rates of HBV. Globally, five percent of those with chronic hepatitis B infection also have hepatitis D and 12.5% of people with HIV are also co-infected with hepatitis D. [57] [42]
Hepatitis D virus was first reported in 1977 as a nuclear antigen in patients infected with HBV who had severe liver disease. [58] This nuclear antigen was then thought to be a hepatitis B antigen and was called the delta antigen. Subsequent experiments in chimpanzees showed that the hepatitis delta antigen (HDAg) was a structural part of a pathogen that required HBV infection to produce a complete viral particle. [59] The entire genome was cloned and sequenced in 1986. It was subsequently placed in its own genus: Deltavirus. [60] [61]
Lábrea fever | |
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Other names | Lábrea's black fever, Lábrea hepatitis, Santa Marta fever |
Specialty | Infectious disease |
Usual onset | sudden |
Duration | approx. 1 week |
Prevention | HBV vaccination |
Prognosis | death |
Lábrea fever is a lethal tropical infection discovered in the 1950s in the city of Lábrea, in the Brazilian Amazon basin, where it occurs mostly in the area south of the Amazon River, in the states of Acre, Amazonas, and Rondônia. The disease has also been diagnosed in Colombia and Peru. It is now known to be a coinfection or superinfection of hepatitis B (HBV) with hepatitis D. [62]
Lábrea fever has a sudden onset, with jaundice, anorexia (lack of appetite), hematemesis (vomiting of blood), headache, fever and severe prostration. Death occurs by acute liver failure (ALF). In the last phase, neurological symptoms such as agitation, delirium, convulsions and hemorrhagic coma commonly appear. These symptoms arise from a fulminant hepatitis which may kill in less than a week, and which characteristically affects children and young adults, and more males than females. It is accompanied also by an encephalitis in many cases. The disease is highly lethal: in a study carried out in 1986 at Boca do Acre, also in the Amazon, 39 patients out of 44 died in the acute phase of the disease. [62] Survivors may develop chronic disease.[ citation needed ]
The main discovery of delta virus and HBV association was done by Gilberta Bensabath, of the Instituto Evandro Chagas, of Belém, state of Pará, and her collaborators. [63]
Infected patients show extensive destruction of liver tissue, with steatosis of a particular type (microsteatosis, characterized by small fat droplets inside the cells), and infiltration of large numbers of inflammatory cells called morula cells, comprised mainly by macrophages containing delta virus antigens. [64]
In the 1987 Boca do Acre study, scientists did an epidemiological survey and reported delta virus infection in 24% of asymptomatic HBV carriers, 29% of acute nonfulminant hepatitis B cases, 74% of fulminant hepatitis B cases, and 100% of chronic hepatitis B cases. [62] The delta virus seems to be endemic in the Amazon region. [65]
Three genotypes (I–III) were originally described. Genotype I has been isolated in Europe, North America, Africa and some Asia. Genotype II has been found in Japan, Taiwan, and Yakutia (Russia). Genotype III has been found exclusively in South America (Peru, Colombia, and Venezuela). Some genomes from Taiwan and the Okinawa islands have been difficult to type but have been placed in genotype 2. However it is now known that there are at least 8 genotypes of this virus (HDV-1 to HDV-8). [66] Phylogenetic studies suggest an African origin for this pathogen. [35]
An analysis of 36 strains of genotype 3 estimated that the most recent common ancestor of these strains originated around 1930. [67] This genotype spread exponentially from early 1950s to the 1970s in South America. The substitution rate was estimated to be 1.07×10−3 substitutions per site per year. Another study [68] found an overall evolution rate of 3.18×10−3 substitutions per site per year. The mutation rate varied with position : the hypervariable region evolved faster (4.55×10−3 substitutions per site per year) than the hepatitis delta antigen coding region (2.60×10−3 substitutions per site per year) and the autocatalytic region (1.11×10−3 substitutions per site per year). A third study suggested a mutation rate between 9.5×10−3 to 1.2×10−3 substitutions/site/year. [69]
Genotypes, with the exception of type 1, appear to be restricted to certain geographical areas: HDV-2 (previously HDV-IIa) is found in Japan, Taiwan and Yakutia; HDV-4 (previously HDV-IIb) in Japan and Taiwan; HDV-3 in the Amazonian region; HDV-5, HDV-6, HDV-7 and HDV-8 in Africa. [70] Genotype 8 has also been isolated from South America. This genotype is usually only found in Africa and may have been imported into South America during the slave trade. [71]
HDV-specific CD8+ T cells can control the virus, but it has been found HDV mutates to escape detection by CD8+ T cells. [72]
A few other viruses with similarity to HDV have been described in species other than humans. Unlike HDV, none of them depend on a Hepadnaviridae (HBV family) virus to replicate. These agents have rod-like structure, a delta antigen, and a ribozyme. [73] HDV and all such relatives are classified in their own realm, Ribozyviria , by the International Committee on Taxonomy of Viruses. [11]
Hepadnaviridae is a family of viruses. Humans, apes, and birds serve as natural hosts. There are currently 18 species in this family, divided among 5 genera. Its best-known member is hepatitis B virus. Diseases associated with this family include: liver infections, such as hepatitis, hepatocellular carcinomas, and cirrhosis. It is the sole accepted family in the order Blubervirales.
Viral hepatitis is liver inflammation due to a viral infection. It may present in acute form as a recent infection with relatively rapid onset, or in chronic form, typically progressing from a long-lasting asymptomatic condition up to a decompensated hepatic disease and hepatocellular carcinoma (HCC).
Rabies virus, scientific name Rabies lyssavirus, is a neurotropic virus that causes rabies in animals, including humans. It can cause violence, hydrophobia, and fever. Rabies transmission can also occur through the saliva of animals and less commonly through contact with human saliva. Rabies lyssavirus, like many rhabdoviruses, has an extremely wide host range. In the wild it has been found infecting many mammalian species, while in the laboratory it has been found that birds can be infected, as well as cell cultures from mammals, birds, reptiles and insects. Rabies is reported in more than 150 countries and on all continents except Antarctica. The main burden of disease is reported in Asia and Africa, but some cases have been reported also in Europe in the past 10 years, especially in returning travellers.
A satellite is a subviral agent that depends on the coinfection of a host cell with a helper virus for its replication. Satellites can be divided into two major classes: satellite viruses and satellite nucleic acids. Satellite viruses, which are most commonly associated with plants, are also found in mammals, arthropods, and bacteria. They encode structural proteins to enclose their genetic material, which are therefore distinct from the structural proteins of their helper viruses. Satellite nucleic acids, in contrast, do not encode their own structural proteins, but instead are encapsulated by proteins encoded by their helper viruses. The genomes of satellites range upward from 359 nucleotides in length for satellite tobacco ringspot virus RNA (STobRV).
Murine coronavirus (M-CoV) is a virus in the genus Betacoronavirus that infects mice. Belonging to the subgenus Embecovirus, murine coronavirus strains are enterotropic or polytropic. Enterotropic strains include mouse hepatitis virus (MHV) strains D, Y, RI, and DVIM, whereas polytropic strains, such as JHM and A59, primarily cause hepatitis, enteritis, and encephalitis. Murine coronavirus is an important pathogen in the laboratory mouse and the laboratory rat. It is the most studied coronavirus in animals other than humans, and has been used as an animal disease model for many virological and clinical studies.
A helper dependent virus, also termed a gutless virus, is a synthetic viral vector dependent on the assistance of a helper virus in order to replicate, and can be used for purposes such as gene therapy. Naturally-occurring satellite viruses are also helper virus dependent, and can sometimes be modified to become viral vectors.
The hepatitis delta virus (HDV) ribozyme is a non-coding RNA found in the hepatitis delta virus that is necessary for viral replication. Hepatitis delta virus is the only known human virus that utilizes ribozyme activity to infect its host. The ribozyme acts to process the RNA transcripts to unit lengths in a self-cleavage reaction during replication of the hepatitis delta virus, which is thought to propagate by a double rolling circle mechanism. The ribozyme is active in vivo in the absence of any protein factors and was the fastest known naturally occurring self-cleaving RNA at the time of its discovery.
Hepatitis B is an infectious disease caused by the hepatitis B virus (HBV) that affects the liver; it is a type of viral hepatitis. It can cause both acute and chronic infection.
HBx is a hepatitis B viral protein. It is 154 amino acids long and interferes with transcription, signal transduction, cell cycle progress, protein degradation, apoptosis and chromosomal stability in the host. It forms a heterodimeric complex with its cellular target protein, and this interaction dysregulates centrosome dynamics and mitotic spindle formation. It interacts with DDB1 redirecting the ubiquitin ligase activity of the CUL4-DDB1 E3 complexes, which are intimately involved in the intracellular regulation of DNA replication and repair, transcription and signal transduction.
HBcAg is a hepatitis B viral protein. It is an indicator of active viral replication; this means the person infected with Hepatitis B can likely transmit the virus on to another person.
Hepatitis B virus (HBV) is a partially double-stranded DNA virus, a species of the genus Orthohepadnavirus and a member of the Hepadnaviridae family of viruses. This virus causes the disease hepatitis B.
cccDNA is a special DNA structure that arises during the propagation of some viruses in the cell nucleus and may remain permanently there. It is a double-stranded DNA that originates in a linear form that is ligated by means of DNA ligase to a covalently closed ring. In most cases, transcription of viral DNA can occur from the circular form only. The cccDNA of viruses is also known as episomal DNA or occasionally as a minichromosome.
The transmission of hepadnaviruses between their natural hosts, humans, non-human primates, and birds, including intra-species host transmission and cross-species transmission, is a topic of study in virology.
A precore mutant is a variety of hepatitis B virus that does not produce hepatitis B virus e antigen (HBeAg). These mutants are important because infections caused by these viruses are difficult to treat, and can cause infections of prolonged duration and with a higher risk of liver cirrhosis. The mutations are changes in DNA bases from guanine to adenine at base position 1896 (G1896A), and from cytosine to thymine at position 1858 (C1858T) in the precore region of the viral genome.
Aichivirus A formerly Aichi virus (AiV) belongs to the genus Kobuvirus in the family Picornaviridae. Six species are part of the genus Kobuvirus, Aichivirus A-F. Within Aichivirus A, there are six different types including human Aichi virus, canine kobuvirus, murine kobuvirus, Kathmandu sewage kobuvirus, roller kobuvirus, and feline kobuvirus. Three different genotypes are found in human Aichi virus, represented as genotype A, B, and C.
Nonstructural protein 5A (NS5A) inhibitors are direct acting antiviral agents (DAAs) that target viral proteins, and their development was a culmination of increased understanding of the viral life cycle combined with advances in drug discovery technology. However, their mechanism of action is complex and not fully understood. NS5A inhibitors were the focus of much attention when they emerged as a part of the first curative treatment for hepatitis C virus (HCV) infections in 2014. Favorable characteristics have been introduced through varied structural changes, and structural similarities between NS5A inhibitors that are clinically approved are readily apparent. Despite the recent introduction of numerous new antiviral drugs, resistance is still a concern and these inhibitors are therefore always used in combination with other drugs.
Ground squirrel hepatitis virus, abbreviated GSHV, is a partially double-stranded DNA virus that is closely related to human Hepatitis B virus (HBV) and Woodchuck hepatitis virus (WHV). It is a member of the family of viruses Hepadnaviridae and the genus Orthohepadnavirus. Like the other members of its family, GSHV has high degree of species and tissue specificity. It was discovered in Beechey ground squirrels, Spermophilus beecheyi, but also infects Arctic ground squirrels, Spermophilus parryi. Commonalities between GSHV and HBV include morphology, DNA polymerase activity in genome repair, cross-reacting viral antigens, and the resulting persistent infection with viral antigen in the blood (antigenemia). As a result, GSHV is used as an experimental model for HBV.
The woolly monkey hepatitis B virus (WMHBV) is a viral species of the Orthohepadnavirus genus of the Hepadnaviridae family. Its natural host is the woolly monkey (Lagothrix), an inhabitant of South America categorized as a New World primate. WMHBV, like other hepatitis viruses, infects the hepatocytes, or liver cells, of its host organism. It can cause hepatitis, liver necrosis, cirrhosis, and hepatocellular carcinoma. Because nearly all species of Lagothrix are threatened or endangered, researching and developing a vaccine and/or treatment for WMHBV is important for the protection of the whole woolly monkey genus.
The epidemiology of hepatitis D occurs worldwide. Although the figures are disputed, a recent systematic review suggests that up to 60 million individuals could be infected. The major victims are the carriers of the hepatitis B surface antigen (HBsAg), who become superinfected by the HDV, and intravenous drug users who are the group at highest risk. The infection usually results in liver damage ; this is most often a chronic and severe hepatitis rapidly conducive to cirrhosis.
Francis "Frank" Vincent Chisari is a physician, experimental pathologist, and viral immunologist, known for his research on virus-host interactions and disease pathogenesis during hepatitis B and hepatitis C virus infections.
MYR Pharmaceuticals receives Conditional Marketing Authorisation by the European Commission for bulevirtide in the European Union for Hepatitis B and D