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'''Measles''' is an infectious viral disease that occurs most often in the late winter and spring. It begins with a [[fever]] that lasts for a couple of days, followed by a cough, runny nose, and conjunctivitis (pink eye). A rash starts on the face and upper neck, spreads down the back and trunk, then extends to the arms and hands, as well as the legs and feet. After about five days, the rash fades the same order it appeared.
{{Taxobox | color=violet
| name = x
| virus_group = x
| familia = x
| genus = x
| sero_complex = x
| subdivision_ranks = Species
| subdivision =
}}


==Description and significance==
Infected people are usually contagious from about four days before their rash starts to appear. The virus resides in the mucus in the nose and throat of infected people. When they sneeze or cough, droplets spray into the air and remain active and highly contagious on infected surfaces for up to two hours.  
Describe the appearance, habitat, etc. of the organism, and why it is important enough to have its genome sequenced.  Describe how and where it was isolated.
Include a picture or two (with sources) if you can find them.


==Genome structure==
Although measles itself is unpleasant, the complications are more dangerous. Six to 20 percent of the people who get the disease will get an ear infection, [[diarrhea]], or [[pneumonia]] (which occurs in up to 6% of reported measles casa and accounts for 60% of deaths from measles). One out of 1000 people with measles will develop inflammation of the [[brain]], and about one out of 1000 will die.
Describe the size and content of the genome.  How many chromosomes?  Circular or linear?  Other interesting features?  What is known about its sequence?
Does it have any plasmids?  Are they important to the organism's lifestyle?


==Cell structure and metabolism==
This disease is rarely seen in children below 3 years of age. It is most unusual before 6 months due to the protection provided by the mother's antibodies acquired while in the womb. After 6 months of age these antibodies start waning and a child becomes susceptible to measles.
Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.


==Ecology==
The measles virus is a cytopathic [[virus]] belonging to the family ''Paramyxoviridae'', genus ''Morbillivirus''. The virus continues to be an important human [[pathogen]]. Although it is largely controlled by [[immunisation]] in developed countries, it causes significant morbidity and mortality in developing ones.
Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.


==Pathology==
== Origins and discovery ==
How does this organism cause disease?  Human, animal, plant hosts?  Virulence factors, as well as patient symptoms.
The measles virus is believed to have evolved from [[rinderpest]] (or a similar animal virus) 4000-5000 years ago, when [[Babylonia]]n cities grew large enough to support continuous person-to-person transmission and thus maintain the virus.  


==Application to Biotechnology==
Reports of measles go as far back to at least 600 B.C. However, the first scientific description of the disease and its distinction from [[smallpox]] is attributed to the [[Persia]]n physician Ibn Razi (Rhazes) 860-932, who published a book entitled ''The Book of Smallpox and Measles'' (in Arabic: ''Kitab fi al-jadari wa-al-hasbah''). In 1954, measles appeared in the [[United States of America]] and with it the beliefs that the virus migrates indirectly or directly from [[Europe]], [[Africa]], and [[Asia]].
Does this organism produce any useful compounds or enzymes?  What are they and how are they used?


==Current Research==
== Causes and symptoms ==
{| class="wikitable" style="float:right"
| Group  || Group V ((-)ssRNA)
|-
| Order  || ''Mononegavirales''
|-
| Family || ''Paramyxoviridae''
|-
| Genus  || ''Morbillivirus''
|}
Measles is caused by a type of virus called paramyxovirus. It is an extremely contagious infection, spread through the tiny droplets that may spray into the air when an individual carrying the virus sneezes or coughs. About 85% of those people exposed to the virus will become infected with it. About 95% of those people infected with the virus will develop the illness called measles. Once someone is infected with the virus, it takes about 7-18 days before he or she actually becomes ill. The most contagious time period is the three to five days before symptoms begin through about four days after the characteristic measles rash has begun to appear.


Enter summaries of the most recent research here--at least three required
The classical symptoms of measles include:
* a fever for at least three days
* high fever&mdash;up to {{convert|40|°C|°F|0}}
* the three "C"s: cough, coryza (runny nose), and conjunctivitis (pink or red eyes)
* tiny white spots inside the month known as Koplik's spot
* a red, slightly bumpy rash
* red, swollen, and sore throat


==References==
The rash is classically described as a generalised, maculopapular, erythematous rash that begins several days after the fever starts. It starts on the head before spreading to cover most of the body, often causing itching. The rash is said to "stain", changing color from red to dark brown, before disappearing.
<references/>


Summary of measles virus  
A measles case is usually confirmed with a blood test for measles antibodies, though if a person with symptoms is a known contact of a confirmed case, a clinical diagnosis is sufficient. The measles virus can be cultured from infected respiratory secretions, the eye, the blood, or the urine during the acute phase of the illness. The usual reason to recover measles virus from a person is to identify the viral strain in order to trace the source of an importation.
 
== Complications and effects ==
It suppresses the immunity and makes the child prone to getting pneumonia and diarrhea. Many patients (about 5-15%) develop other complications such as ear infections and sinus infections, especially in children. Other viral infections may also strike the patient, including croup, [[bronchitis]], [[laryngitis]], or viral pneumonia. Inflammation of the [[liver]], [[appendix]], [[intestine]], or [[lymph node]]s within the [[abdomen]] may cause other complications. Rarely, inflammations of the [[heart]] or [[kidney]]s, a drop in platelet count (causing episodes of difficult-to-control bleeding), or reactivation of an old tuberculosis infection can occur.
 
An extremely serious complication of measles infection is the swelling of the brain ([[encephalitis]]). This can occur up to several weeks after the basic measles symptoms have resolved. About one out of every thousand patients develops this complication, and about 10-15% of these patients die. Symptoms include fever, headache, sleepiness, seizures, and [[coma]]. Long-term problems following recovery from measles encephalitis may include seizures and mental retardation.


Measles is a highly contagious viral infection characterized by a fever and a red, bumpy rash.  
Because of limited disease surveillance and death registration in many countries with weak infrastructure and high measles burden, current routine reporting systems are inadequate for monitoring global measles mortality.<ref>[http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5408a4.htm Progress in Reducing Measles Mortality --- Worldwide, 1999--2003] cdc.gov</ref> Different modeling approaches have been used to estimate the global number of measles deaths. Overall, in roughly last 150 years, measles has been estimated to have killed about 200 million people worldwide.


What is going on in the body?
== Prevention ==
Measles is acquired by coming into contact with infected respiratory secretions and droplets. Infected people can spread it when they cough, sneeze or wipe their noses. Over the last four decades, widespread use of a highly effective measles vaccine and aggressive outbreak control have resulted in the elimination of measles virus circulation in the United States. However, measles is imported into this country periodically by travelers, visitors, and immigrants.  
There is no specific treatment for measles. However, measles can be prevented by immunisation. About 95% of vaccinated persons are protected with one dose, and practically everyone is protected with two doses. Licensed vaccines to prevent the disease became available in 1963. All children, including those who were born before 1979, should be vaccinated to protect themselves and others from measles.


What are the signs and symptoms of the infection?
On the basis of results from the natural history model, overall global measles mortality decreased 39%, from 873,000 deaths (uncertainty bounds: 645,000-1,196,000 deaths) in 1999 to 530,000 deaths (bounds: 383,000-731,000 deaths) in 2003. The largest reduction was in Africa, where estimated measles mortality decreased by 46% during this period.  
Symptoms usually begin about 1 to 1-1/2 weeks after acquiring the virus. The symptoms can include:
• A fever, usually 39-40 degrees C or higher (103 -104 degree F)
• A red, slightly bumpy rash.
• cough.
• Tiny white spots inside the mouth (known as "Koplik's spots")
• Runny nose (Coryza)
• Conjunctivitis, also known as pink or red eye. Conjunctivitis is an inflammation of the mucous membrane that lines the inner part of the eyelid.
*Sometimes, measles cases can be complicated by ear infections, croup, or pneumonia. About 0.1% of patients can contract encephalitis, an infection of the brain after becoming infected with measles. Encephalitis can result in brain damage and, sometimes, death.  


What are the causes and risks of the infection?
In the early 2000s the MMR vaccine controversy in the [[United Kingdom]] regarding a potential link between the combined MMR vaccine (vaccinating children from mumps, measles and rubella) and autism prompted a comeback in the measles party, where parents deliberately infect the child with measles to build up the child's immunity without an injection. This practice poses many health risks to the child, and has been discouraged by the public health authorities. Scientific evidence provides no support for the hypothesis that MMR plays a role in causing autism. Declining immunisation rates in the UK are the probable cause of a significant increase of cases of measles, 2006 being the highest on record, and 2007 already showing an increase on the previous year.
Measles is caused by the measles virus, which belongs to the Paramyxovirus family of viruses. Anyone who has not had measles before, and has not been immunized, is at risk for measles. Measles is so highly communicable by airborne spread that cases have been shown to result from sitting in a waiting room occupied by a measles case hours before.  


What can be done to prevent the infection?
If measles is suspected, a health care provider should be contacted. The health care provider can confirm the diagnosis and provide home care instructions to relieve the discomfort of the symptoms.
The measles vaccine is very effective at preventing measles in immunized people. The vaccine is usually combined with the rubella, mumps, and chickenpox vaccines and given as one shot, called the MMRV vaccine. Side effects of the MMRV vaccine can include:
• fever and rash
• joint pain
• allergic reactions
Other side effects are rare. The vaccine should not be given to pregnant women or to women who are planning on getting pregnant in the 3 months following immunization. Another way to prevent the spread of infection is to isolate the infected person. An infected person with a normal immune system should stay home from school or work for 4 days after the rash appears. An infected person with autoimmune problems, where the body attacks its own tissues, may be contagious for even longer. In some circumstances, susceptible individuals who have been exposed to measles are also isolated, until it is determined whether they will come down with the infection. Some people with autoimmune problems or other immune system disorders should not have the measles vaccine. If these unprotected people are exposed to an infected person, they should receive immune globulin prophylaxis, an injection of disease-fighting proteins.  


How is the infection diagnosed?
== References ==
A measles case is usually confirmed with a blood test for measles antibodies, though if a person with symptoms is a known contact of a confirmed case, a clinical diagnosis is sufficient. The measles virus can be cultured from infected respiratory secretions, the eye, the blood, or the urine during the acute phase of the illness. The usual reason to recover measles virus from a person is to identify the viral strain in order to trace the source of an importation.
<references />[[Category:Suggestion Bot Tag]]

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Measles is an infectious viral disease that occurs most often in the late winter and spring. It begins with a fever that lasts for a couple of days, followed by a cough, runny nose, and conjunctivitis (pink eye). A rash starts on the face and upper neck, spreads down the back and trunk, then extends to the arms and hands, as well as the legs and feet. After about five days, the rash fades the same order it appeared.

Infected people are usually contagious from about four days before their rash starts to appear. The virus resides in the mucus in the nose and throat of infected people. When they sneeze or cough, droplets spray into the air and remain active and highly contagious on infected surfaces for up to two hours.

Although measles itself is unpleasant, the complications are more dangerous. Six to 20 percent of the people who get the disease will get an ear infection, diarrhea, or pneumonia (which occurs in up to 6% of reported measles casa and accounts for 60% of deaths from measles). One out of 1000 people with measles will develop inflammation of the brain, and about one out of 1000 will die.

This disease is rarely seen in children below 3 years of age. It is most unusual before 6 months due to the protection provided by the mother's antibodies acquired while in the womb. After 6 months of age these antibodies start waning and a child becomes susceptible to measles.

The measles virus is a cytopathic virus belonging to the family Paramyxoviridae, genus Morbillivirus. The virus continues to be an important human pathogen. Although it is largely controlled by immunisation in developed countries, it causes significant morbidity and mortality in developing ones.

Origins and discovery

The measles virus is believed to have evolved from rinderpest (or a similar animal virus) 4000-5000 years ago, when Babylonian cities grew large enough to support continuous person-to-person transmission and thus maintain the virus.

Reports of measles go as far back to at least 600 B.C. However, the first scientific description of the disease and its distinction from smallpox is attributed to the Persian physician Ibn Razi (Rhazes) 860-932, who published a book entitled The Book of Smallpox and Measles (in Arabic: Kitab fi al-jadari wa-al-hasbah). In 1954, measles appeared in the United States of America and with it the beliefs that the virus migrates indirectly or directly from Europe, Africa, and Asia.

Causes and symptoms

Group Group V ((-)ssRNA)
Order Mononegavirales
Family Paramyxoviridae
Genus Morbillivirus

Measles is caused by a type of virus called paramyxovirus. It is an extremely contagious infection, spread through the tiny droplets that may spray into the air when an individual carrying the virus sneezes or coughs. About 85% of those people exposed to the virus will become infected with it. About 95% of those people infected with the virus will develop the illness called measles. Once someone is infected with the virus, it takes about 7-18 days before he or she actually becomes ill. The most contagious time period is the three to five days before symptoms begin through about four days after the characteristic measles rash has begun to appear.

The classical symptoms of measles include:

  • a fever for at least three days
  • high fever—up to 40 °C (104 °F)
  • the three "C"s: cough, coryza (runny nose), and conjunctivitis (pink or red eyes)
  • tiny white spots inside the month known as Koplik's spot
  • a red, slightly bumpy rash
  • red, swollen, and sore throat

The rash is classically described as a generalised, maculopapular, erythematous rash that begins several days after the fever starts. It starts on the head before spreading to cover most of the body, often causing itching. The rash is said to "stain", changing color from red to dark brown, before disappearing.

A measles case is usually confirmed with a blood test for measles antibodies, though if a person with symptoms is a known contact of a confirmed case, a clinical diagnosis is sufficient. The measles virus can be cultured from infected respiratory secretions, the eye, the blood, or the urine during the acute phase of the illness. The usual reason to recover measles virus from a person is to identify the viral strain in order to trace the source of an importation.

Complications and effects

It suppresses the immunity and makes the child prone to getting pneumonia and diarrhea. Many patients (about 5-15%) develop other complications such as ear infections and sinus infections, especially in children. Other viral infections may also strike the patient, including croup, bronchitis, laryngitis, or viral pneumonia. Inflammation of the liver, appendix, intestine, or lymph nodes within the abdomen may cause other complications. Rarely, inflammations of the heart or kidneys, a drop in platelet count (causing episodes of difficult-to-control bleeding), or reactivation of an old tuberculosis infection can occur.

An extremely serious complication of measles infection is the swelling of the brain (encephalitis). This can occur up to several weeks after the basic measles symptoms have resolved. About one out of every thousand patients develops this complication, and about 10-15% of these patients die. Symptoms include fever, headache, sleepiness, seizures, and coma. Long-term problems following recovery from measles encephalitis may include seizures and mental retardation.

Because of limited disease surveillance and death registration in many countries with weak infrastructure and high measles burden, current routine reporting systems are inadequate for monitoring global measles mortality.[1] Different modeling approaches have been used to estimate the global number of measles deaths. Overall, in roughly last 150 years, measles has been estimated to have killed about 200 million people worldwide.

Prevention

There is no specific treatment for measles. However, measles can be prevented by immunisation. About 95% of vaccinated persons are protected with one dose, and practically everyone is protected with two doses. Licensed vaccines to prevent the disease became available in 1963. All children, including those who were born before 1979, should be vaccinated to protect themselves and others from measles.

On the basis of results from the natural history model, overall global measles mortality decreased 39%, from 873,000 deaths (uncertainty bounds: 645,000-1,196,000 deaths) in 1999 to 530,000 deaths (bounds: 383,000-731,000 deaths) in 2003. The largest reduction was in Africa, where estimated measles mortality decreased by 46% during this period.

In the early 2000s the MMR vaccine controversy in the United Kingdom regarding a potential link between the combined MMR vaccine (vaccinating children from mumps, measles and rubella) and autism prompted a comeback in the measles party, where parents deliberately infect the child with measles to build up the child's immunity without an injection. This practice poses many health risks to the child, and has been discouraged by the public health authorities. Scientific evidence provides no support for the hypothesis that MMR plays a role in causing autism. Declining immunisation rates in the UK are the probable cause of a significant increase of cases of measles, 2006 being the highest on record, and 2007 already showing an increase on the previous year.

If measles is suspected, a health care provider should be contacted. The health care provider can confirm the diagnosis and provide home care instructions to relieve the discomfort of the symptoms.

References