Yellow fever

Definition

Yellow fever is a viral infection transmitted by mosquitoes.

Causes

Yellow fever is caused by a small virus that is spread by the bite of mosquitoes. This disease is common in South America and in sub-Saharan Africa.

Anyone can get yellow fever, but the elderly have a higher risk of severe infection. If a person is bitten by an infected mosquito, symptoms usually develop 3 - 6 days later.

Yellow fever has three stages:

1. Early stage: Headache, muscle aches, fever, loss of appetite, vomiting, and jaundice are common. After approximately 3 - 4 days, often symptoms go away briefly (remission).
2. Period of remission: After 3 -4 days, fever and other symptoms go away. Most people will recover at this stage, but others may move onto the third, most dangerous stage (intoxication stage) within 24 hours.
3. Period of intoxication: Multi-organ dysfunction occurs. This includes liver and kidney failure, bleeding disorders/hemorrhage, brain dysfunction including delirium, seizures, coma, shock, and death.

References

Bryan CS. Yellow fever in the Americas. Infect Dis Clin North Am. 2004; 18(2): 275-92.

Cohen J, Powderly WG. Infectious Diseases. 2nd ed. New York, NY: Elsevier; 2004:2095-2098.

Mandell GL, Bennett JE, Dolin R. Principles and Practice of Infectious Diseases. 6th ed. London: Churchill Livingstone; 2005.

Auerbach PS. Wilderness Medicine. 4th ed. St. Louis, Mo: Mosby; 2001:1578-1580.