Yellow Fever. What is yellow fever?.
Yellow fever is a viral hemorrhagic disease spread between humans, as well as between certain other primates and humans, by the bite of yellow fever-infected mosquitoes. The virus is called simply Yellow fever virus and belongs to the virus family Flaviviridae.
The majority of persons infected with yellow fever virus have no illness or only mild illness.
In persons who develop symptoms, the incubation period (time from infection until illness) is typically 3–6 days.
The initial symptoms include sudden onset of fever, chills, severe headache, back pain, general body aches, nausea, and vomiting, fatigue, and weakness. Most persons improve after the initial presentation.
After a brief remission of hours to a day, roughly 15% of cases progress to develop a more severe form of the disease. The severe form is characterized by high fever, jaundice, bleeding, and eventually shock and failure of multiple organs.
The disease is not spread directly from person to person. It is spread by the bite of an infective Aedesaegyptimosquito. A mosquito that bites a person with yellow fever within the first five days of illness may transmit the disease to other people it bites later.
Mortality varies from 50% without medical treatment to about 5% with first-world medical care. Individuals recover or die from yellow fever in 7 to 12 days. Death usually occurs between the sixth and tenth day. Those who recover have life-long immunity. Weakness may prolong convalescence for 2 to 3 weeks. Initial prognosis is always guarded since a sudden change for the worse is common.
Since there is no cure for the viral infection itself, medical treatment of yellow fever focuses on easing symptoms such as fever, muscle pain, and dehydration. Because of the risk of internal bleeding, avoid aspirin and other nonsteroidal anti-inflammatory drugs if you suspect you have yellow fever. Hospitalization is often needed.
Yellow fever can be prevented by vaccination. Travelers should also take precautions against mosquito bites when in areas with yellow fever transmission. Travelers should get vaccinated for yellow fever before visiting areas where yellow fever is found. If you continue to live or travel in yellow fever-endemic areas, you should receive a booster dose of yellow fever vaccine after 10 years.
Yellow fever continues to occur in regions of Africa and South America, despite the availability of effective vaccines. Recently, some cases of severe neurologic disease and multiorgan system disease have been described in individuals who received yellow fever vaccine
Bioterrorists want a horrible disease that is easy to spread and that has a high fatality rate. So, thought terrorists during the Civil War, what better disease than yellow fever? It kills within days, causing a hemorrhagic fever that makes victims bleed from the mouth and nose and vomit a black substance that resembles coffee grounds but consists largely of dried blood.
There was no effective treatment for yellow fever and no way to prevent it, and it could spread rapidly through a city, causing panic and social disruption.
1st slide and 1st picture http://www.historyofvaccines.org/content/timelines/yellow-fever2nd slidehttp://www.cdc.gov/yellowfever/symptoms/2nd picturehttp://viraldiseasesd.wikispaces.com/Yellow+Fever3rd slidehttp://www.vdh.state.va.us/epidemiology/factsheets/Yellow_Fever.htm4th slidehttps://www.mdguidelines.com/yellow-fever/prognosis5th slidehttp://www.webmd.com/a-to-z-guides/yellow-fever-symptoms-treatment?page=26th slide and picturehttp://www.cdc.gov/VACCINES/vpd-vac/yf/default.htm7th slidehttp://cid.oxfordjournals.org/content/44/6/850.full8th slidehttp://www.health.gov.au/yellowfever9th slidehttp://www.nytimes.com/2001/11/13/health/new-york-was-bioterrorism-target-in-1864.html