|
Herpesvirus
''Orthoherpesviridae'', previously named and more widely known as ''Herpesviridae'', is a large family of DNA viruses that cause infections and certain diseases in animals, including humans. The members of this family are commonly known as herpesviruses. The family name is derived from the Greek word ἕρπειν ( 'to creep'), referring to spreading cutaneous lesions, usually involving blisters, seen in flares of herpes simplex 1, herpes simplex 2 and herpes zoster ( shingles). In 1971, the International Committee on the Taxonomy of Viruses (ICTV) established ''Herpesvirus'' as a genus with 23 viruses among four groups. Since then, the number of identified herpesviruses has grown to more than 100. Herpesviruses can cause both latent and lytic infections. Nine herpesvirus types are known to primarily infect humans, at least five of which are extremely widespread among most human populations, and which cause common diseases: herpes simplex 1 and 2 (HSV-1 and HSV-2, also know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Herpesvirus 6
Human herpesvirus 6 (HHV-6) is the common collective name for human herpesvirus 6A (HHV-6A) and human herpesvirus 6B (HHV-6B). These closely related viruses are two of the nine known herpesviruses that have humans as their primary host. HHV-6A and HHV-6B are double-stranded DNA viruses within the ''Betaherpesvirinae'' subfamily and of the genus '' Roseolovirus''. HHV-6A and HHV-6B infect almost all of the human populations that have been tested. HHV-6A has been described as more neurovirulent, and as such is more frequently found in patients with neuroinflammatory diseases such as multiple sclerosis. HHV-6 (and HHV-7) levels in the brain are also elevated in people with Alzheimer's disease. HHV-6B primary infection is the cause of the common childhood illness exanthema subitum (also known as roseola infantum or sixth disease). It is passed on from child to child. It is uncommon for adults to contract this disease as most people have had it by kindergarten, and once contract ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Herpesvirus 7
Human herpesvirus 7 (HHV-7) is one of nine known members of the ''Herpesviridae'' family that infects humans. HHV-7 is a member of ''Betaherpesvirinae'', a subfamily of the ''Herpesviridae'' that also includes HHV-6 and ''Cytomegalovirus'' (HHV-5 or HCMV). HHV-7 often acts together with HHV-6, and the viruses together are sometimes referred to by their genus, '' Roseolovirus''. HHV-7 was first isolated in 1990 from CD4+ T cells taken from peripheral blood lymphocytes. Signs and symptoms Both HHV-6B and HHV-7, as well as other viruses, can cause a skin condition in infants known as exanthema subitum, although HHV-7 causes the disease less frequently than HHV-6B. HHV-7 infection also leads to or is associated with a number of other symptoms, including acute febrile respiratory disease, fever, rash, vomiting, diarrhea, low lymphocyte counts, and febrile seizures, though most often no symptoms present at all. There are indications that HHV-7 can contribute to the development ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herpes Simplex Virus
Herpes simplex virus 1 and 2 (HSV-1 and HSV-2) are two members of the Herpesviridae#Human herpesvirus types, human ''Herpesviridae'' family, a set of viruses that produce Viral disease, viral infections in the majority of humans. Both HSV-1 and HSV-2 are very common and Infectious disease, contagious. They can be spread when an infected person begins viral shedding, shedding the virus. As of 2016, about 67% of the world population under the age of 50 had HSV-1. In the United States, about 47.8% and 11.9% are estimated to have HSV-1 and HSV-2, respectively, though actual prevalence may be much higher. Because it can be transmitted through any intimate contact, it is one of the most common sexually transmitted infections. Symptoms Many of those who are infected never develop symptoms. Symptoms, when they occur, may include watery blisters in the Human skin, skin of any location of the body, or in mucous membranes of the mouth, lips, nose, genitals, or eyes (herpes simplex ker ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roseola
Roseola, also known as sixth disease, is an infectious disease caused by certain types of human herpes viruses. Most infections occur before the age of three. Symptoms vary from absent to the classic presentation of a fever of rapid onset followed by a rash. The fever generally lasts for three to five days, while the rash is generally pink and lasts for less than three days. Complications may include febrile seizures, with serious complications being rare. It is caused by '' human herpesvirus 6'' (HHV-6A, HHV-6B) or '' human herpesvirus 7'' (HHV-7). Spread is usually through the saliva of those who are otherwise healthy. However, it may also spread from the mother to the baby during pregnancy. Diagnosis is typically based on symptoms and does not need to be confirmed with blood tests (PCR or antigen). Low numbers of white blood cells may also be present. Treatment includes sufficient fluids and medications to treat the fever. Nearly all people are infected at some point. Mal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alphaherpesvirinae
''Alphaherpesvirinae'' is a subfamily of viruses in the family ''Herpesviridae'', primarily distinguished by reproducing more quickly than other subfamilies in the ''Herpesviridae''. In animal virology the most important herpesviruses belong to the Alphaherpesvirinae. Pseudorabies virus is the causative agent of Aujeszky's disease in pigs, and '' Bovine herpesvirus 1'' is the causative agent of bovine infectious rhinotracheitis and pustular vulvovaginitis. Mammals serve as natural hosts. There are currently 45 species in this subfamily, divided among 5 genera, with one species unassigned to a genus. Diseases associated with this subfamily include: HHV-1 and HHV-2: skin vesicles or mucosal ulcers, rarely encephalitis and meningitis, HHV-3: chickenpox (varicella) and shingles, GaHV-2: Marek's disease. Genera ''Alphaherpesvirinae'' consists of the following five genera: * '' Iltovirus'' * ''Mardivirus'' * '' Scutavirus'' * '' Simplexvirus'' * '' Varicellovirus'' The species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virus Latency
Virus latency (or viral latency) is the ability of a pathogenic virus to lie dormant ( latent) within a cell, denoted as the lysogenic part of the viral life cycle. A latent viral infection is a type of persistent viral infection which is distinguished from a chronic viral infection. Latency is the phase in certain viruses' life cycles in which, after initial infection, proliferation of virus particles ceases. However, the viral genome is not eradicated. The virus can reactivate and begin producing large amounts of viral progeny (the lytic part of the viral life cycle) without the host becoming reinfected by new outside virus, and stays within the host indefinitely. Virus latency is not to be confused with clinical latency during the incubation period when a virus is ''not'' dormant. Mechanisms Episomal latency Episomal latency refers to the use of genetic episomes during latency. In this latency type, viral genes are stabilized, floating in the cytoplasm or nucl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aujeszky's Disease
Aujeszky's disease, usually called pseudorabies in the United States, is a viral disease in swine that is endemic in most parts of the world. It is caused by pseudorabies virus (PRV). Aujeszky's disease is considered to be the most economically important viral disease of swine in areas where classical swine fever ( hog cholera) has been eradicated. Other mammals, such as cattle, sheep, goats, cats, dogs, and raccoons, are also susceptible. The disease is usually fatal in these animal species. Research on PRV in pigs has pioneered animal disease control with genetically modified vaccines. PRV is now used in model studies of basic processes during lytic herpesvirus infection, and for unravelling molecular mechanisms of herpesvirus neurotropism. History In 1902, a Hungarian veterinarian, Aladár Aujeszky, demonstrated a new infectious agent in a dog, ox, and cat, and showed it caused the same disease in swine and rabbits. In the following decades the infection was found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chickenpox
Chickenpox, also known as varicella ( ), is a highly contagious disease caused by varicella zoster virus (VZV), a member of the herpesvirus family. The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab over. It usually starts on the chest, back, and face. It then spreads to the rest of the body. The rash and other symptoms, such as fever, tiredness, and headaches, usually last five to seven days. Complications may occasionally include pneumonia, inflammation of the brain, and bacterial skin infections. The disease is usually more severe in adults than in children. Chickenpox is an airborne disease which easily spreads via human-to-human transmission, typically through the coughs and sneezes of an infected person. The incubation period is 10–21 days, after which the characteristic rash appears. It may be spread from one to two days before the rash appears until all lesions have crusted over. It may also spread through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Virus
A DNA virus is a virus that has a genome made of deoxyribonucleic acid (DNA) that is replicated by a DNA polymerase. They can be divided between those that have two strands of DNA in their genome, called double-stranded DNA (dsDNA) viruses, and those that have one strand of DNA in their genome, called single-stranded DNA (ssDNA) viruses. dsDNA viruses primarily belong to two realms: ''Duplodnaviria'' and ''Varidnaviria'', and ssDNA viruses are almost exclusively assigned to the realm ''Monodnaviria'', which also includes some dsDNA viruses. Additionally, many DNA viruses are unassigned to higher taxa. Reverse transcribing viruses, which have a DNA genome that is replicated through an RNA intermediate by a reverse transcriptase, are classified into the kingdom '' Pararnavirae'' in the realm ''Riboviria''. DNA viruses are ubiquitous worldwide, especially in marine environments where they form an important part of marine ecosystems, and infect both prokaryotes and eukaryotes. They a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pustular Vulvovaginitis
Bovine alphaherpesvirus 1 (BoHV-1) is a virus of the family ''Herpesviridae'' and the subfamily ''Alphaherpesvirinae'', known to cause several diseases worldwide in cattle, including rhinotracheitis, vaginitis, balanoposthitis, abortion, conjunctivitis, and enteritis. BoHV-1 is also a contributing factor in shipping fever, also known as bovine respiratory disease (BRD). It is spread horizontally through sexual contact, artificial insemination, and aerosol transmission and it may also be transmitted vertically across the placenta. BoHV-1 can cause both clinical and subclinical infections, depending on the virulence of the strain. Although these symptoms are mainly non-life-threatening it is an economically important disease as infection may cause a drop in production and affect trade restrictions. Like other herpesviruses, BoHV-1 causes a lifelong latent infection and sporadic shedding of the virus. The sciatic nerve and trigeminal nerve are the sites of latency. A reactiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
