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Enteroviruses
''Enterovirus'' is a genus of positive-sense single-stranded RNA viruses 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 realized that there were significant overlaps in the biological properties of viruses in the different groups. Enteroviruses isolated more recently are named with a system of consecutive numbers: EV-D68, EV-B69, EV-D70, EV-A71, etc., where genotyp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Flaccid Myelitis
Acute flaccid myelitis (AFM) is a serious condition of the spinal cord. Symptoms include rapid onset of arm or leg weakness and decreased reflexes. Difficulty moving the eyes, speaking, or swallowing may also occur. Occasionally, numbness or pain may be present. Complications can include trouble breathing. The cause of most cases is unclear as of 2018. More than 90% of recent cases have followed a mild viral infection such as from enteroviruses. While polio can cause AFM, since 2014, it has not been involved in cases in the United States. The underlying mechanism involves damage to the spinal cord's grey matter. Diagnosis may be supported by medical imaging of the spine, nerve conduction studies, and cerebrospinal fluid testing. Treatment involves supportive care. Physical therapy may be recommended. Occasionally, mechanical ventilation is required to support breathing. Outcomes are variable. The condition is rare and occurs most commonly in children. Fewer than one in 500,000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterovirus 68
Enterovirus D68 (EV-D68) is a member of the ''Picornaviridae'' family, an enterovirus. First isolated in California in 1962 and once considered rare, it has been on a worldwide upswing in the 21st century. It is suspected of causing a polio-like disorder called acute flaccid myelitis (AFM). Virology EV-D68 is one of the more than one hundred types of enteroviruses, a group of ssRNA viruses containing the polioviruses, coxsackieviruses, and echoviruses. It is unenveloped. Unlike all other enteroviruses, EV-D68 displays acid lability and a lower optimum growth temperature, both characteristic features of the human rhinoviruses. It was previously called human rhinovirus 87 by some researchers. Since the year 2000, the original virus strains diversified and evolved a genetically distinct outbreak strain, clade B1. It is Clade B1, but not older strains, which has been associated with AFM and is neuropathic in animal models. Epidemiology Since its discovery in 1962, EV-D68 had ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterovirus A71
Enterovirus 71 (EV71), also known as Enterovirus A71 (EV-A71), is a virus of the genus ''Enterovirus'' in the ''Picornaviridae'' family, notable for its role in causing epidemics of severe neurological disease and hand, foot, and mouth disease in children. It was first isolated and characterized from cases of neurological disease in California in 1969. Enterovirus 71 infrequently causes polio-like syndrome permanent paralysis. Evolution This virus is a member of the enterovirus species A. Species A was formerly assigned to the genus ''Rhinovirus''. This virus appears to have evolved only recently with the first known strain isolated in 1965. It was associated with an outbreak of neurological disease in the United States in 1969. It then spread to Europe with outbreaks there in Bulgaria (1975) and Hungary (1978). It has since spread to various countries in Asia where it has been responsible for several outbreaks, most recently in Cambodia (2012). The strains fall into six genogr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picornavirus
Picornaviruses are a group of related nonenveloped RNA viruses which infect vertebrates including fish, mammals, and birds. They are viruses that represent a large family of small, positive-sense, single-stranded RNA viruses with a 30 nm icosahedral capsid. The viruses in this family can cause a range of diseases including the common cold, poliomyelitis, meningitis, hepatitis, and paralysis. Picornaviruses constitute the family ''Picornaviridae'', order ''Picornavirales'', and realm ''Riboviria''. There are 158 species in this family, assigned to 68 genera. Notable examples are genera ''Enterovirus'' (including ''Rhinovirus'' and ''Poliovirus''), '' Aphthovirus'', '' Cardiovirus'', and '' Hepatovirus''. Etymology The name "picornavirus" has a dual etymology. Firstly, the name derives from ''picorna''- which is an acronym for "''p''oliovirus, ''i''nsensitivity to ether, ''c''oxsackievirus, ''o''rphan virus, ''r''hinovirus, and ribo''n''ucleic ''a''cid". Secondly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterovirus 71
Enterovirus 71 (EV71), also known as Enterovirus A71 (EV-A71), is a virus of the genus ''Enterovirus'' in the ''Picornaviridae'' family, notable for its role in causing epidemics of severe neurological disease and hand, foot, and mouth disease in children. It was first isolated and characterized from cases of neurological disease in California in 1969. Enterovirus 71 infrequently causes polio-like syndrome permanent paralysis. Evolution This virus is a member of the enterovirus species A. Species A was formerly assigned to the genus ''Rhinovirus''. This virus appears to have evolved only recently with the first known strain isolated in 1965. It was associated with an outbreak of neurological disease in the United States in 1969. It then spread to Europe with outbreaks there in Bulgaria (1975) and Hungary (1978). It has since spread to various countries in Asia where it has been responsible for several outbreaks, most recently in Cambodia (2012). The strains fall into six genogr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aseptic Meningitis
Aseptic meningitis is the inflammation of the meninges, a membrane covering the brain and spinal cord, in patients whose cerebral spinal fluid test result is negative with routine bacterial cultures. Aseptic meningitis is caused by viruses, mycobacteria, spirochetes, fungi, medications, and cancer malignancies. The testing for both meningitis and aseptic meningitis is mostly the same. A cerebrospinal fluid sample is taken by lumbar puncture and is tested for leukocyte levels to determine if there is an infection and goes on to further testing to see what the actual cause is. The symptoms are the same for both meningitis and aseptic meningitis but the severity of the symptoms and the treatment can depend on the certain cause. The most common cause of aseptic meningitis is by viral infection. Other causes may include side-effects from drugs and connective tissue disorders. Signs and symptoms Aseptic meningitis is a disease that can depend on the patient's age, however, res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poliovirus
A poliovirus, the causative agent of polio (also known as poliomyelitis), is a serotype of the species ''Enterovirus C'', in the family of '' Picornaviridae''. There are three poliovirus serotypes: types 1, 2, and 3. Poliovirus is composed of an RNA genome and a protein capsid. The genome is a single-stranded positive-sense RNA (+ssRNA) genome that is about 7500 nucleotides long. The viral particle is about 30 nm in diameter with icosahedral symmetry. Because of its short genome and its simple composition—only RNA and a nonenveloped icosahedral protein coat that encapsulates it—poliovirus is widely regarded as the simplest significant virus. Poliovirus was first isolated in 1909 by Karl Landsteiner and Erwin Popper. The structure of the virus was first elucidated in 1958 using X-ray diffraction by a team at Birkbeck College led by Rosalind Franklin, showing the polio virus to have icosahedral symmetry. In 1981, the poliovirus genome was published by two different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coxsackie A Virus
Coxsackie A virus (CAV) is a cytolytic Coxsackievirus of the ''Picornaviridae'' family, an enterovirus (a group containing the polioviruses, coxsackieviruses, and echoviruses). Viral structure and genome Coxsackie A virus is a subgroup of enterovirus A, which are small, non-enveloped, positive-sense, single-stranded RNA viruses. Its protective, icosahedral capsid has an external portion that contains sixty copies of viral proteins (VP1,-2,-3) and an internal portion surrounding the RNA genome containing sixty copies of VP4 viral proteins. This capsid mediates cell entry and elicits the humoral immune responses. Enteroviruses have a depression encircling each fivefold axis (canyon), which is their binding site for immunoglobulin-like receptors. This binding can trigger viral expansion and release of its genome. A complete genome analysis of Coxsackie virus A2, A4, A5, and A10 strains isolated from individuals with hand-foot-mouth disease showed that natural recombination is f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flaccid Paralysis
Flaccid paralysis is a neurological condition characterized by weakness or paralysis and reduced muscle tone without other obvious cause (e.g., trauma). This abnormal condition may be caused by disease or by trauma affecting the nerves associated with the involved muscles. For example, if the somatic nerves to a skeletal muscle are severed, then the muscle will exhibit flaccid paralysis. When muscles enter this state, they become limp and cannot contract. This condition can become fatal if it affects the respiratory muscles, posing the threat of suffocation. It also occurs in spinal shock stage in complete transection of spinal cord occurred in injuries like gunshots injuries.Saladin, Kenneth S. Anatomy & Physiology: The Unity of Form and Function. McGraw-Hill. 6th Edition. 2012. Causes Polio and other viruses The term ''acute flaccid paralysis'' (AFP) is often used to describe an instance with a sudden onset, as might be found with polio. AFP is the most common sign of ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coxsackie B Virus
Coxsackie B is a group of six serotypes of coxsackievirus (CVB1-CVB6), a pathogenic enterovirus, that trigger illness ranging from gastrointestinal distress to full-fledged pericarditis and myocarditis (coxsackievirus-induced cardiomyopathy). The genome of Coxsackie B virus consists of approximately 7,400 base pairs. Geographic distribution The various members of the Coxsackie B group were discovered almost entirely in the United States, appearing originally in Connecticut, Ohio, New York, and Kentucky, although a sixth member of the group has been found in the Philippines. However, all six serotypes have a global distribution and are a relatively common cause of gastrointestinal upset. The name reflects the first isolation from Coxsackie, New York. Transmission Infections are most commonly spread by the oral-fecal route, emphasizing the importance of good hygiene, especially hand-washing. Oral-oral and respiratory droplets can also be means of transmission. Epidemiolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjunctivitis
Conjunctivitis, also known as pink eye, is inflammation of the outermost layer of the white part of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may occur. The affected eye may have increased tears or be "stuck shut" in the morning. Swelling of the white part of the eye may also occur. Itching is more common in cases due to allergies. Conjunctivitis can affect one or both eyes. The most common infectious causes are viral followed by bacterial. The viral infection may occur along with other symptoms of a common cold. Both viral and bacterial cases are easily spread between people. Allergies to pollen or animal hair are also a common cause. Diagnosis is often based on signs and symptoms. Occasionally, a sample of the discharge is sent for culture. Prevention is partly by handwashing. Treatment depends on the underlying cause. In the majority of viral cases, there is no specific treatment. Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myocarditis
Myocarditis, also known as inflammatory cardiomyopathy, is an acquired cardiomyopathy due to inflammation of the heart muscle. Symptoms can include shortness of breath, chest pain, decreased ability to exercise, and an irregular heartbeat. The duration of problems can vary from hours to months. Complications may include heart failure due to dilated cardiomyopathy or cardiac arrest. Myocarditis is most often due to a viral infection. Other causes include bacterial infections, certain medications, toxins and autoimmune disorders. A diagnosis may be supported by an electrocardiogram (ECG), increased troponin, heart MRI, and occasionally a heart biopsy. An ultrasound of the heart is important to rule out other potential causes such as heart valve problems. Treatment depends on both the severity and the cause. Medications such as ACE inhibitors, beta blockers, and diuretics are often used. A period of no exercise is typically recommended during recovery. Corticosteroi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
