Yellow+Fever

=** By: Mady Romenesko, Meghan Whitman, Zach Graber, and Andrew Palmbach **= = __Introduction to Yellow Fever__ =

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Yellow Fever, also known as "yellow jack", is a viral hemorrhagic disease transmitted by female mosquitoes. The virus is a RNA virus and is common in tropical or subtropical areas. In most cases pain, nausea and fever are common with a chance of a toxic phase to follow. There is a vaccination for prevention that will last the average person for ten years. In some countries, epidemics of Yellow Fever have been known to occur. In unvaccinated areas there have been 200,000 illnesses and 30,000 deaths reported. The treatment that does exist hasn't proven very useful and there is no cure. Yellow Fever has been titled a re-emerging disease as it has become more common again since the 1980s. For more general information on Yellow Fever please see [|Yellow Fever - Wikipedia]. **Figure 1** shows the Yellow Fever mosquito. =====

[[image:Yellow_Fever_Mosquito.jpg width="222" height="144" align="right" caption="Figure 1: Yellow Fever Mosquito"]]
= __History of Yellow Fever__ = The origins of Yellow Fever are predicted to be in East or Central Africa and eventually spread to West Africa. It was likely spread to North and South America by ship during the slave trade. Yellow Fever can cause major outbreaks. The first written evidence of an outbreak occurred in Yucatan in 1648. It is unknown who first discovered Yellow Fever, but in 1881 Carlos Finlay, (shown in **Figure** 2), issued proof that the virus was carried by mosquitoes, not human interaction. It’s transmitted through a bite into a human or other species. (See below in //How the Yellow Fever Virus Spreads// for more information on the transmission of the virus.) Later, Walter Reed confirmed Finlay's theory.

Early Cures
The first vaccine against yellow fever was developed by Max Theiler in the 1930s. This vaccine is based off of the discoveries of Reed and Finlay. Also, in 1902 Reed and his sanitary engineers killed off the entire mosquito species in Cuba. The vaccine helped control or eliminate yellow fever in other countries in South America and Africa too. While Theiler was studying the virus, he got infected. Luckily, he recovered and became immune to it. His experience helped make the prevention vaccine work better. Theiler was awarded the 1951 Nobel Prize for Physiology or Medicine for this brilliant discovery.

Outbreak
The Yellow Fever virus came to Philadelphia in 1793, which at that time was America’s largest city. It was the capital and a very busy port. During summer that year, the climate was unusually hot and dry and the water levels of the streams and wells were reduced dangerously. This provided a great place for insects to breed. People in Philadelphia, during July, were astounded by the number of flies and mosquitoes that swarmed the docking area. Later that month refugees piled in by the thousands, escaping the political chaos in the Caribbean Islands. Unaware of what they were doing, the Caribbean refugees brought Yellow Fever into America. Philadelphia’s numerous mosquitoes provided a vehicle for spreading the disease by biting an infected person and getting the disease. Then the mosquito will travel to a healthy person and transfer the disease into them, too. The first few deaths appeared also in the month of July and steadily increased. Symptoms would start with pain to the head, back and limbs and included a high fever also. They would disappear, but shortly return with a more severe fever and turn the victim’s skin yellow while they vomited black clots of blood. The victim would helplessly become unconscious and die. For more information on this outbreak, check out [|Yellow Fever Attacks Philadelphia, 1793].

= __How the Yellow Fever Virus Spreads__ = Yellow Fever spreads by the bite of mosquitoes. The mosquito is known as the Yellow Fever Mosquito or Aedes Aegypti by its Latin name. These mosquitoes lay their eggs in damp closed areas including jars, pots, crevices, cans, rain water containers, old tires or any nooks and crannies they can find. The Yellow Fever Mosquito will feed only during the daytime and prefers busy urban areas. These mosquitoes prefer human blood over animals for an unknown reason. Yellow Fever is not contagious, meaning that it is not passed directly from human to human. These mosquitoes are able to breed in standing water versus other mosquitoes that can only breed and thrive in rainforests, so they can come close to human environments and infect them. Take a look at **Figure 3** for a look at what the bite does to the inside of the human arm. Also take a look at the **Figure 4** diagram which shows the ways the virus spreads in its most prevalent areas. 

= __Symptoms of Yellow Fever__ = There are three stages of yellow fever. The three stages have different symptoms, which are listed below and shown in **Figure 5**.

First Stage
During the first stage of severe yellow fever, symptoms include many common flu symptoms, as well as some other symptoms such as:


 * High Fever (up to 108 degrees Fahrenheit)
 * Headache
 * Light-Headed
 * Seizures (More common in children)
 * Pain in the neck and back
 * Vomiting
 * Bloody nose
 * Feeling nauseous
 * Muscle and joint pain

Second Stage
Most people recover during the second stage. The symptoms lessen, but a few new ones may appear during the second stage. They include:
 * Anuria (inability to release urine)
 * Bleeding
 * Confusion

Third Stage
Most people don't get to the third stage, but if you do it is a very nasty stage. Symptoms include:


 * Yellowing of the skin and eyes
 * Continuous nose bleeds
 * Blood in your stool
 * Vomiting blood
 * Kidney, heart, and liver failure
 * Shock
 * Death

= __Where Yellow Fever is Prevalent__ = Yellow Fever is most prevalent in sub-Saharan Africa and South America, where it causes about 30,000 deaths every year. There are a few projects directed towards those areas to help prevent the disease from occurring, so hopefully it will help the areas affected. See **Figure 6** for more detail on the affected areas.

= = = = = __Treatment for Yellow Fever__ = There is no cure for yellow fever. You can prevent yellow fever by getting a vaccination and wearing long-sleeved shirts and pants while in an area where the disease is common. For more information on the recommended vaccination see [|VaccinationInfo - MedTerms]. Use mosquito netting, shown in **Figure 7**, if you are in a place where the transmitting mosquito lives and if you have air-conditioning available it is recommended to use it. If you are in an area where yellow fever is common or likely to occur you should look into prevention and make sure you are prepared in case of another deadly outbreak.

====Although no cure is out there, there are treatments for the symptoms. In the first stage, where dizziness, headaches, and nausea are common symptoms, you can use acetaminophen, (not aspirin), rest in bed, and drink lots of fluids. For more severe symptoms such as confusion, anuria, vomiting blood and jaundice (yellowing of the skin), you can have intravenous (IV) fluids, medications for seizures, nausea and vomiting you can take prevention for secondary infections such as pneumonia or urinary tract infections and good nursing care always makes things better. The diagram in **Figure 8** below shows the predictable places for the Yellow Fever virus to occur. If you live in any of these areas, you should probably consider the prevention tips listed above. ====

[[image:Mosquito_on_Netting.jpg caption="Figure 7: Mosquito on Mosquito Netting"]]
= = = __References__ = //Carlos Finlay//. N.d. //Infection Landscapes//. Awesome, Inc., n.d. Web. 28 Feb. 2012. . “Definition of Yellow Fever Vaccination.” //MedicineNet.com//. MedicineNet, Inc., 10 Aug. 2000. Web. 23 Feb. 2012. . DemandMedia. “How to Prevent Yellow Fever.” //eHow//. N.p., 1999-2012. Web. 22 Feb. 2012. . //Figure 1//. N.d. //Centers for Disease Control and Prevention//. N.p., n.d. Web. 28 Feb. 2012. . //Mosquito on Netting//. 2012. //bd Aftersale Services//. N.p., n.d. Web. 28 Feb. 2012. . Rymaruk, Jen. //Mosquito Bite//. N.d. //EmpowHER//. HW, LLC d/‌b/‌a EmpowHER Media, n.d. Web. 28 Feb. 2012. . Schoenstadt, Arthur. “Yellow Fever Treatment.” //eMed TV//. N.p., 2006-2012. Web. 22 Feb. 2012. . //There are typically three distinct phases of the clinical presentation of yellow fever://. N.d. //Infection Landscapes//. Awesome, Inc., n.d. Web. 28 Feb. 2012. . //Transmission cycles of yellow fever in Africa and South America. Adapted from Annu Rev Entomol. 2007. 52:209-29.// . N.d. //Medscape Reference//. WebMD LLC, n.d. Web. 27 Feb. 2012. . //Where is yellow fever virus HOT?!// N.d. //TextMed//. The Research Foundation of State University of New York Computer Science Department at Stony Brook University, n.d. Web. 28 Feb. 2012. . “Who Discovered Yellow Fever.” //Yellow Fever//. Yellow fever, n.d. Web. 23 Feb. 2012. <http://www.yellowfeverinfo.com/‌who-discovered-yellow-fever/>. “Yellow Fever.” //Travel Health.co.UK//. N.p., 21 Nov. 2006. Web. 22 Feb. 2012. <http://www.travelhealth.co.uk/‌diseases/‌yellowfever.htm>. “Yellow fever.” //Wikitravel//. MediaWiki, 27 Aug. 2011. Web. 23 Feb. 2012. <http://wikitravel.org/‌en/‌Yellow_fever>. “Yellow Fever.” //Wkipedia//. N.p., 15 Feb. 2012. Web. 22 Feb. 2012. <http://en.wikipedia.org/‌wiki/‌Yellow_fever>. “Yellow Fever Attacks Philadelphia, 1793.” //Eyewitness to History//. Ibis Communications, Inc., 2005. Web. 27 Feb. 2012. <http://www.eyewitnesstohistory.com/‌yellowfever.htm>. //The Yellow Fever Mosquito (Aedes aegypti)//. N.d. //Biogents Mosquitaire//. N.p., n.d. Web. 27 Feb. 2012. <http://www.mosquitaire.com/‌cms/‌website.php?id=/‌en/‌tigermosquitos/‌yellow.htm>. = =

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