3.+Measles

=__Measles Overview__ =
 * //Julia and Anna's Chapter//**

//"When measles attack a generation who has never been exposed to the measles virus previously, nearly everyone becomes infected."//- Michael B. Oldstone

Measles is a virus which is transmitted through the air. Infected droplets are released by talking, coughing, and sneezing. This common childhood disease can now be prevented with a vaccine but prior to this, it had been a fatal disease for a very long time. Up until 1960 this virus was very common in young children. Some of the main signs of measles include cough, runny nose, inflamed eyes, sore throat, fever and a red, blotchy skin rash. This disease can be highly fatal for small children. Although death rates have been falling due to the measles vaccine, several hundred thousand people a year are still killed by the measles, most of those people being under the age of 5 years old.
 * **Basic Overview**

Measles was carried to the Americas by European colonies who were immune, this virus helped wipe out the Native American population and it is highly contagious.  //The following video recording is a clip of Dr. Samuel Katz, the creator of the measles vaccine, talking about the measles. This is an excellent video and gives great information on symptoms of the measles, the measles vaccine, and general information about the measles disease itself.//

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 * **Symptoms [[image:measles_rash_back.jpg width="360" height="270" align="right"]]**

Fever, Dry cough, Runny nose, Conjunctivitis, Sensitivity to light, Koplik's spots (tiny white spots with bluish-white centers found inside the mouth on the inner lining of the cheek), and a skin rash made up of large, flat blotches that often flow into one another.

One of the main effects that the measles has on the human body is that it cripples the human immune system. It can also cause reactivation and rapid spread of any former diseases the person had.




 * **Course of the measles virus**

The virus travels through the respiratory system and airways, the virus lives off of the energy from the new host. The virus lives in the host for 10-14 days, the host suffers a high fever, a rash, runny nose, watery eyes, sometimes pink eye. The Rash typically starts behind the ears and along the hairline, then travels to the rest of the face and down the body. After the virus is through, the host will never suffer measles again. Lower respiratory tract (lungs and bronchi) are more susceptible than the nose-to-throat canal to Measles infection.

During the intial 2-4 days after infection, the virus replicates in local areas of the respiratory cells. It then spreads to draining lymph nodes where a second round of the virus is produced. The virus enters the bloodstream carried within white cells of the blood. The virus continues to circulate in the blood through a process called Viremia, and it carries the infection to many parts of the body causing mild coughing and fever.

The infected person does not feel sick so the incubation and infection periods go unnoticed for the most part.

In the second phase of the measles, which occurs after 8-12 days, the infected person usually experiences fever, weakness, and loss of appetite. They can also experience coughing and running of the nose and eyes. During the second phase of the Measles, there is a much higher level of viremia. Also, small blood vessels start to get infected and a rash can occur. The cough will then often increase in intensity as will the fever. A fever often spikes to a temperature of 104 or 105 degrees Fahrenheit

Measles is caused by a highly contagious virus that lives in the nose and throat of an infected human which is its primary host. The infected human is contagious from four days before the rash appears until four days after it appears. When an infected person coughs, sneezes, or talks, infected droplets spray into the air and other people can inhale them. If the droplets are not inhaled, they can land on surfaces and remain active for many hours before they die, and people can contract the virus by putting their fingers in their mouthes or rubbing their eyes after touching the infected surface.
 * **Causes**

There is not one specific treatment that can get rid of a pre-established measles infection, but there are a few measures people can take to protect others who may have been exposed to the virus. A few of these measures include:
 * **Treatments**
 * 1) Post-exposure vaccination- may be effective for up to 72 hours after exposure to the virus.
 * 2) Immune Serum globulin- injections of proteins received by pregnant women, infants, and people with weak immune systems.
 * 3) Analgesics- over the counter medications.
 * 4) Antibiotics
 * 5) Isolation

If the host has a weak immune system that can lead to complications such as: Ear infections Pneumonia Bronchitis Diarrhea Seizures Hearing loss Enlarged Spleen Swollen lymph nodes Liver inflammation Eye ulcers
 * **Fun Facts**

Infants are very vulnerable to this virus because their immune system is not fully developed and they do not receive the vaccine until they are 12-15 months old.  In the 15th century measles was usually contracted with smallpox, a deadly pair.  3000 BC- Measles may have first appeared with the growth of cities in the middle east. Seventh Century AD- Earliest references made to measles. Tenth Century- Measles is scientifically described and differentiated from smallpox by Persian born Ibn Razi. Late 15th and 16th centuries- Measles is introduced to the New World by European explorers, devastating many Native American populations. 1757- Scottish physician Francis Home demonstrates that measles is caused by an infectious agent present in the blood of patients. 1846- Danish physician Peter Panum studies a measles outbreak in the Faroe Islands and shows that the disease is acquired solely by direct transmission. He also describes the measles incubation period and lifetime immunity from it. 1941- In the United States, 894,134 cases of measles are reported, resulting in 2,250 deaths. 1954- John Enders and Thomas Peebles report the first successful isolation and propagation of the measles virus in human and monkey kidney cells. This leads to Ender's development of the measles' vaccine in the late 1950's. 1966-1968- Almost 20 million doses of the measles vaccine are given to children in the US and the number of cases decreases dramatically. 1978- Doctors in the US begin giving children a combined vaccine against measles, mumps, and rubella. 1989- Large increase in the measles cases indicates failure of the vaccine to provide lifelong immunity and leads to the introduction of a measles booster shot. 2001- The lowest number of measles cases (116) ever reported in the US, resulting in only one death. 2003- Worldwide, there are an estimated 30 million measles cases and 700,000 deaths each year. More than half of the deaths occur in Africa. In countries and regions of the world that are able to keep vaccination coverage high, measles are very rare.
 * **Timeline**

__Bibliograpy__ 

__**Pictograpy**__ http://dckaleidoscope.wordpress.com/2009/04/21/measles-found-in-metropolitan-area/ http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=105x7666166 http://www.ihealthtopics.com/2008/11/05/the-measles-virus/