Dictionary:
ech·o·vi·rus (ĕk'ō-vī'rəs) 
|
[e(nteric) c(ytopathogenic) h(uman) o(rphan) virus.]
| 5min Related Video: echovirus |
| Sci-Tech Encyclopedia: Echovirus |
One of the divisions of the enterovirus subgroup, within the picornavirus group of viruses. The name is derived from the term enteric cytopathogenic human orphan virus. More than 34 antigenic types exist. Only certain types have been associated with human illnesses, particularly with aseptic meningitis and febrile disease. Their epidemiology is similar to that of other enteroviruses. Echoviruses resemble polioviruses and coxsackieviruses in size (about 28 nanometers) and in many other properties. Diagnosis is made by isolation and typing of the viruses in tissue culture. Antibodies form during convalescence. See also Animal virus; Enterovirus; Picornaviridae.
| Dental Dictionary: echoviruses |
An enteric pathogen associated with fever and mild respiratory disease; sometimes may produce an aseptic meningitis.
| Veterinary Dictionary: echovirus |
Some viruses, which were originally considered nonpathogenic, in the family Picornaviridae, genus Enterovirus. The name is derived from the first letters of the description ‘enteric cytopathogenic human orphan’, but similar viruses ECBO and ECPO (for bovine and porcine, respectively, and other species) are also recognized. At the time of the isolation of the viruses the diseases they caused were not known, hence the term ‘orphan’, but it is now known that some of these viruses produce many different types of human disease, especially aseptic meningitis, and diarrhea and various respiratory diseases. The members of the group are now included in the enteroviruses.
| Wikipedia: Echovirus |
| Echovirus | |
|---|---|
| Virus classification | |
| Group: | Group IV ((+)ssRNA) |
| Family: | Picornaviridae |
| Genus: | Enterovirus |
| Species: | Human enterovirus B |
| Subtype | |
|
Echovirus |
|
An echovirus is a type of RNA virus that belongs to the genus Enterovirus of the Picornaviridae family.[1] Echoviruses are found in the gastrointestinal tract (hence it being part of the enterovirus genus) and exposure to the virus causes other opportunistic infections and diseases.
Contents |
The first isolation of echoviruses occurred from the feces of asymptomatic children early in the 1950s, just after cell culturing had been developed. The echo– part of the name was originally an acronym for "enteric cytopathic human orphan" virus: Orphan virus means a virus that is not associated with any known disease. Even though Echoviruses have since been identified with various diseases, the original name is still used.[2]
Echovirus is highly infectious, and its primary target is children. The echovirus is among the leading causes of acute febrile illness in infants and young children, and is the most common cause of aseptic meningitis.[3] Infection of an infant with this virus following birth may cause severe systemic diseases, and is associated with high infant mortality rates. The echovirus can mimic symptoms caused by other common bacterial and viral infections.
An echovirus measures 24-30 nanometres (nm), and is similar to other viruses, since it has a naked protein capsid, which makes up 75% of the virus particle that encloses a dense central core of single-stranded RNA. This RNA has a length of approximately 7.5 kilobase (kb), contains an RNA replicase, viral-coded proteins, and a single polyprotein that is responsible for the formation of structural proteins and other proteins necessary for cellular replication. The structural proteins determine host range and play a very important role in delivering the RNA genome into the cytoplasm of new host cells.[3]
Some viral replication of an echovirus occurs in the nasopharynx after infection and then spreads to regional lymph nodes. However, most viral particles are swallowed and they reach the lower gut tract, where the virus is presumed to bind to specific receptors. The virus then spreads to the lower intestinal tract, replicating but not causing any major cellular effects along the way. Next, the virus spreads to many secondary sites in the body such as the central nervous system, liver, spleen, bone marrow, heart and finally the lungs. Additional replication of the virus will occur, causing symptoms 4 to 6 days after infection. The most deadly part however is delayed when symptoms of a central nervous system disease start to appear. Enteroviruses are capable of infecting any cell in the body. These viruses are highly infectious. They can spread through the air to other hosts 1–3 weeks after infection and can spread through feces to other hosts eight weeks after infection.
Echovirus disease occurs disproportionately in males. Infection within the first two weeks of birth can cause devastating and potentially fatal disease. In this population, death usually results from overwhelming liver failure or myocarditis, rather than infection of the central nervous system. Older children and adults have a better prognosis. Myocarditis is the most frequent complication in adults.
Echovirus infections can occur in people of all age groups. However, as we get older, there is increased production of specific antibodies to the echovirus. Several studies performed during epidemics show that infants become infected at notably higher rates than older children and adults.
Causes of echovirus infections can be placed in several categories. Main causes of infection are from overcrowded conditions such as the poor districts of a city and poor hygiene. Echoviruses are transmitted person-to-person; the fecal-oral route is the predominant mode, although transmission sometimes occurs via respiration of oral secretions such as saliva. Indirect transmission occurs through numerous routes, including via contaminated water, food, and fomites (inanimate objects). Contaminated swimming and wading pools can also transmit the virus. Also, there are well-documented reports of transmission via the contaminated hands of hospital personnel.
No specific treatment for echovirus infection is currently available. Care is directed at relief of symptoms. The anti-viral drug pleconaril interferes with the binding of the echovirus particle to the cell membrane and the drug also hinders the uncoating of virions by attaching itself to the viral protein capsid.[3] The pharmaceutical company, ViroPharma Incorporated, ended development of pleconaril in 2004.
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)
 | Picornaviridae (virology) |
| Enterovirus (virology) |
| Laryngitis: Causes and symptoms |
 | Can echoviruses cause a rash? |
| What is the life cycle of the echovirus? |
Copyrights:
 |
 | Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved. Read more |
 |
| Sci-Tech Encyclopedia. McGraw-Hill Encyclopedia of Science and Technology. Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved. Read more |
 |
| Dental Dictionary. Mosby's Dental Dictionary. Copyright © 2004 by Elsevier, Inc. All rights reserved. Read more |
|
| Veterinary Dictionary. Saunders Comprehensive Veterinary Dictionary 3rd Edition. Copyright © 2007 by D.C. Blood, V.P. Studdert and C.C. Gay, Elsevier. All rights reserved. Read more |
 |
| Wikipedia. This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article "Echovirus". Read more |
