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Orphan Virus
An orphan virus is a virus that is not associated with a disease but may possess pathogenicity. Some orphan viruses include adeno-associated virus (Parvoviridae), human herpesvirus 7 (Herpesviridae), human foamy virus (Retroviridae), Human Reovirus (Reoviridae), hepatitis G (Flaviviridae), and TT virus (Anelloviridae). Gilbert Dalldorf, a pathologist who showed that Coxsackie viruses paralyze mice but not humans, indicated that the term ‘orphan’ was created "in a moment of conviviality" by a group of virologists.Mortimer, Philip P. "Orphan Viruses, Orphan Diseases: Still the Raw Material for Virus Discovery." Reviews in Medical Virology 23.6 (2013): 337-39. Web. Many enteroviruses are referred to as ECHO, enteric cytopathic human orphan viruses, because they were originally not associated with any disease. Even though many of them are associated with severe diseases, the name ECHO still continues to be used. See also *Novel virus *Reoviridae *Viral metagenomics Viral me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogenicity
In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term ''pathogen'' came into use in the 1880s. Typically, the term ''pathogen'' is used to describe an ''infectious'' microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms, is called microbiology, while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time frames, but soil has the longes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TT Virus
''Alphatorquevirus'' is a Genus (biology), genus of viruses in the family ''Anelloviridae'', in group DNA virus#Group II: ssDNA viruses, II in the Baltimore classification. It encompasses many species of the virus formerly known as TTV, transfusion transmitted virus, or torque teno virus, SENV, SANBAN, and others. The genus contains 26 species. Taxonomy The genus contains the following species: *''Torque teno chlorocebus virus 1'' *''Torque teno chlorocebus virus 2'' *''Torque teno chlorocebus virus 3'' *''Torque teno chlorocebus virus 5'' *''Torque teno virus 1'' *''Torque teno virus 2'' *''Torque teno virus 3'' *''Torque teno virus 4'' *''Torque teno virus 5'' *''Torque teno virus 6'' *''Torque teno virus 7'' *''Torque teno virus 9'' *''Torque teno virus 10'' *''Torque teno virus 13'' *''Torque teno virus 14'' *''Torque teno virus 15'' *''Torque teno virus 17'' *''Torque teno virus 18'' *''Torque teno virus 19'' *''Torque teno virus 20'' *''Torque teno virus 21'' *''Torque teno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viruses
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,Dimmock p. 4 more than 9,000 virus species have been described in detail of the millions of types of viruses in the environment. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles, or ''virions'', consisting of (i) the genetic material, i.e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viral Metagenomics
Viral metagenomics is the study of viral genetic material obtained from environmental DNA samples or clinical DNA samples obtained from a Host (biology), host or natural reservoir. Metagenomic methods can be applied to study viruses in any system and has been used to describe various viruses associated with cancerous tumors, extreme environments, terrestrial ecosystems, and the blood and feces of humans. The term virome is also used to refer to viruses investigated by metagenomic sequencing of viral nucleic acids and is frequently used to describe environmental shotgun metagenomes. Viral metagenomics is a culture independent methodology that provides insights on viral diversity, abundance, and functional potential of viruses within the environment. Viruses lack a universal phylogenetic marker making metagenomics the only way to assess the genetic diversity of viruses in an environmental sample . With the advancements of techniques that can exploit next-generation sequencing, virus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Novel Virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,Dimmock p. 4 more than 9,000 virus species have been described in detail of the millions of types of viruses in the environment. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles, or ''virions'', consisting of (i) the genetic material, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enteric Cytopathic Human Orphan Virus
Echovirus is a polyphyletic group of viruses associated with enteric disease in humans. The name is derived from "enteric cytopathic human orphan virus". These viruses were originally not associated with disease, but many have since been identified as disease-causing agents. The term "echovirus" was used in the scientific names of numerous species, but all echoviruses are now recognized as strains of various species, most of which are in the family ''Picornaviridae''. List of echoviruses Thirty-four echoviruses are known: * Human echoviruses 1–7, 9, 11–21, 24–27, and 29–33 are strains of the species ''Enterovirus B'' of the genus ''Enterovirus''. * Human echovirus 8 was shown to be identical to Human echovirus 1 and was abolished as a species. * Human echovirus 10 was reclassified as a strain of the species ''Reovirus type 1'', currently named ''Mammalian orthoreovirus'' of the genus ''Orthoreovirus'', which belongs to the family ''Reoviridae''. As such, Human echovirus 10 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterovirus
''Enterovirus'' is a genus of positive-sense single-stranded RNA virus An RNA virus is a virusother than a retrovirusthat has ribonucleic acid (RNA) as its genetic material. The nucleic acid is usually single-stranded RNA ( ssRNA) but it may be double-stranded (dsRNA). Notable human diseases caused by RNA viruses ...es associated with several human and mammalian diseases. Enteroviruses are named by their transmission-route through the intestine ('enteric' meaning intestinal). Serologic studies have distinguished 71 human enterovirus serotypes on the basis of antibody neutralization tests. Additional antigenic variants have been defined within several of the serotypes on the basis of reduced or nonreciprocal cross-neutralization between variant strains. On the basis of their pathogenesis in humans and animals, the enteroviruses were originally classified into four groups, polioviruses, Coxsackie A viruses (CA), Coxsackie B viruses (CB), and echoviruses, but it was quickly rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coxsackie Virus
Coxsackieviruses are a few related enteroviruses that belong to the ''Picornaviridae'' family of nonenveloped, linear, positive-sense single-stranded RNA viruses, as well as its genus ''Enterovirus'', which also includes poliovirus and echovirus. Enteroviruses are among the most common and important human pathogens, and ordinarily its members are transmitted by the fecal–oral route. Coxsackieviruses share many characteristics with poliovirus. With control of poliovirus infections in much of the world, more attention has been focused on understanding the nonpolio enteroviruses such as coxsackievirus. Coxsackieviruses are among the leading causes of aseptic meningitis (the other usual suspects being echovirus and mumps virus). The entry of coxsackievirus into cells, especially endothelial cells, is mediated by coxsackievirus and adenovirus receptor. Groups Coxsackieviruses are divided into group A and group B viruses based on early observations of their pathogenicity in neonat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anelloviridae
''Anelloviridae'' is a family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ... of viruses. They are classified as vertebrate viruses and have a non-enveloped capsid, which is round with isometric, icosahedral symmetry and has a triangulation number of 3. The name is derived from Italian ''anello'' 'ring', referring to the circular genome of anelloviruses. Genome The genome is not segmented and contains a single molecule of cccDNA, circular, negative-sense, single-stranded DNA. The complete genome is 3000–4000 nucleotides long. They also contain a non-coding region with one to two 80–110 nt sequences that contain high GC content, forming a secondary structure of stems and loops. The genome has Open reading frame, ORFs and a high degree of genetic diversity. Although the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flaviviridae
''Flaviviridae'' is a family of enveloped positive-strand RNA viruses which mainly infect mammals and birds. They are primarily spread through arthropod vectors (mainly ticks and mosquitoes). The family gets its name from the yellow fever virus; ''flavus'' is Latin for "yellow", and yellow fever in turn was named because of its propensity to cause jaundice in victims. There are 89 species in the family divided among four genera. Diseases associated with the group include: hepatitis (hepaciviruses), hemorrhagic syndromes, fatal mucosal disease (pestiviruses), hemorrhagic fever, encephalitis, and the birth defect microcephaly (flaviviruses). Structure Virus particles are enveloped and spherical with icosahedral-like geometries that have pseudo T=3 symmetry. They are about 40–60 nm in diameter. Genome Members of the family ''Flaviviridae'' have monopartite, linear, single-stranded RNA genomes of positive polarity, and 9.6 to 12.3 kilobase in total length. The 5'-termini of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adeno-associated Virus
Adeno-associated viruses (AAV) are small viruses that infect humans and some other primate species. They belong to the genus ''Dependoparvovirus'', which in turn belongs to the family ''Parvoviridae''. They are small (approximately 26 nm in diameter) replication-defective, nonenveloped viruses and have linear single-stranded DNA (ssDNA) genome of approximately 4.8 kilobases (kb). AAV are not currently known to cause disease. The viruses cause a very mild immune response. Several additional features make AAV an attractive candidate for creating viral vectors for gene therapy, and for the creation of isogenic human disease models. Gene therapy vectors using AAV can infect both dividing and quiescent cells and persist in an extrachromosomal state without integrating into the genome of the host cell. In the native virus, however, integration of virally carried genes into the host genome does occur. Integration can be important for certain applications, but can also have unwan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatitis G
GB virus C (GBV-C), formerly known as hepatitis G virus (HGV) and also known as human pegivirus – HPgV is a virus in the family ''Flaviviridae'' and a member of the ''Pegivirus'', is known to infect humans, but is not known to cause human disease. Reportedly, HIV patients coinfected with GBV-C can survive longer than those without GBV-C, but the patients may be different in other ways. Research is active into the virus' effects on the immune system in patients coinfected with GBV-C and HIV. Human infection The majority of immunocompetent individuals clear GBV-C viraemia, but in some individuals, infection persists for decades. However, the time interval between GBV-C infection and clearance of viraemia (detection of GBV-C RNA in plasma) is not known. About 2% of healthy US blood donors are viraemic with GBV-C, and up to 13% of blood donors have antibodies to E2 protein, indicating possible prior infection. Parenteral, sexual, and vertical transmissions of GBV-C have bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
