Yellow+Fever

= Yellow Fever   Tiffany S. & Tonya C.  =

Description of virus that causes the disease.

 * ** Caused by a "flavivirus" called Yellow Fever **
 * ** (flavus meaning yellow in Latin) **
 * ** Group called Flaviviridae, carried by antropods (mosquitoes, ticks etc.) **
 * ** 40-60 nanometers wide **
 * ** enveloped RNA virus **
 * ** consists of a single strand of RNA **

Viral Specificity:

 * ** Main target is the liver **
 * ** Also affects the heart, kidneys, glands, adrenal glands **
 * ** Skeletal muscle tissue affected **
 * ** Hosts are humans (Urban yellow fever) or monkeys (Jungle yellow fever) **
 * ** After bitten by infected anthropod the virus enters through the skin **
 * ** Travels through the blood stream spreading to the organs **
 * ** Liver failure occurs, heart beat slows and adrenal glands stop functioning **



Symptoms and progression of the disease:

 * ** Incubation period of 3-6 days **
 * ** Symptoms start abruptly (5-6 days) including fever, headache, back pain, extreme exhaustion, nausea, and vomiting. **
 * ** Second phase symptoms such as extreme fever, jaundice (due to liver damage), liver & kidney failure, and bleeding in the mouth, skin, and gastrointestinal tract **
 * ** After 3-4 days of symptoms the host usually begins healing lasting hours to days **
 * ** Then the "Yellow Phase" including severe symptoms such as liver inflammation, jaundice, black vommit, high fever, hemorrhaging, confusion, bleeding into the skin, coma & death **
 * ** If the host recovers from the "Yellow Phase" they go into remission **
 * ** Undergoes a lytic cycle in both the mosquito and human body (liver cells) **



Common Methods of Transmission:

 * ** Transmitted through infected mosquitoes **


 * ** Not passed from human to human **
 * ** Three different infectious cycles **
 * __** Urban cycle: **__
 * ** Human infected in densely populated areas **
 * ** one or many infected mosquitoes pass it to large numbers of humans **
 * ** common cause of yellow fever outbreaks **
 * __** Sylvatic cycle: **__
 * ** in the jungle, monkeys **
 * ** infected monkeys pass the virus to other mosquitoes **
 * ** can rarely occur to humans working in rainforest **
 * __** Savannah cycle: **__
 * ** can infect humans or monkeys **
 * ** in humid areas, most common in Africa **

Treatment and Prevention:

 * ** Yellow fever vaccine exists **
 * ** Avoidance of mosquito bites (covering of exposed skin/repellent) **
 * ** Rest & fluids is crucial to reduce symptoms **
 * ** Hospitalization **
 * ** No cure exsists once acquired **

Miscellaneous:

 * ** 90% of cases occur in Africa, 10% in South America **
 * ** Originated in Africa, spread to West Africa **
 * ** Carried to Yucatan by ship in 1648 **
 * ** For hundreds of years people had no idea what caused Yellow Fever **
 * ** Major outbreaks in South America **
 * ** Carried to United States (mainly Philadelphia) **
 * ** Caused George Washington to flee **

**Author: Mary T. Busowski**

 * Title of article: Yellow Fever**

**Url: []**

 * Date: April 17, 2009**


 * Author: Judy Arbigue**
 * Title of article: Yellow Fever - The Disease & Symptoms**
 * Url: []**
 * Date: February 7, 2007**


 * Author: Mama's Health copyright**
 * Title: Yellow Fever**
 * Url: []**
 * Date: Oct. 23, 2010**