What is yellow fever?

Yellow fever is a viral disease transmitted between humans by a mosquito. It is characterized by an acute onset of fever, hepatitis (inflammation of the liver), and albuminuria (protein in the urine), followed by a brief remission, and then a recurrence of fever, hepatitis, albuminuria, and in some instances, renal (kidney) failure, shock, and generalized hemorrhages (bleeding).

Who gets yellow fever?

Yellow fever occurs only in the tropics. In South America sporadic infections occur almost exclusively in forestry and agricultural workers from occupational exposure in or near forests. In Africa, the virus is transmitted in three regions: 1) in the moist savanna zones of West and Central Africa during the rainy season; 2) in urban locations and villages; and 3) to a lesser extent, in jungle regions.

How is yellow fever spread?

Yellow fever is transmitted between humans by a mosquito.

How soon after exposure do symptoms appear?

Symptoms occur within 3-6 days after infection with the virus.

How is yellow fever diagnosed?

Yellow fever is diagnosed by isolating the yellow fever virus from tissues, blood, or other body fluid, or, for those persons who have not been vaccinated, by measuring specific antibodies in the blood.

What is the treatment for yellow fever?

There is no specific treatment for yellow fever, besides supportive care.

How can yellow fever be prevented?

There are two actions travelers can take to avoid yellow fever: a) General precautions to avoid mosquito bites should be followed by everyone. b) Most adults and children over nine months of age can receive the yellow fever vaccine.

General precautions to avoid mosquito bites include the use of insect repellent, protective clothing, and mosquito netting.

Yellow fever vaccine is a live virus vaccine which has been used for several decades. A single dose confers immunity lasting 10 years or more. The vaccine is only administered at designated yellow fever vaccination centers, the locations of which can usually be given by your local health department. If a person is at continued risk of yellow fever infection, a booster dose is needed every 10 years.

Some countries require travelers to have received yellow fever vaccine within the last 10 years as a condition for entry. These conditions change periodically. Consult with your personal doctor or a travel clinic to learn of the current requirements of the area(s) to which you will be traveling.

Where can I get more information?

UTAH DEPARTMENT OF HEALTH
BUREAU OF EPIDEMIOLOGY
August 2001

This fact sheet was based on the Centers for Disease Control and Prevention's Information on Yellow Fever sheet (last updated 4/2/97).