May also be called: YF

Yellow fever is a viral disease that a person can get from being bitten by an infected mosquito.

More to Know

Yellow fever is caused by a virus carried by mosquitoes. Someone bitten by an infected mosquito might develop symptoms 3-6 days later, but most people don't get sick or have only mild symptoms. If someone does develop symptoms, these can include fever, chills, headache, vomiting, and jaundice (a condition that turns the skin yellow — hence the disease's name). Symptoms often go away after 3-4 days. At that point, most people with yellow fever recover completely.

In about 15% of cases, the person may become sick again within a day or two. This stage of the disease can lead to seizures, organ failure, and internal bleeding. While rare, a case of yellow fever in this stage is a serious life-threatening condition that requires immediate medical attention.

Keep in Mind

Yellow fever usually is found only in tropical areas of Africa and South America. Very few cases happen in the United States. There is no cure for yellow fever, but there is an effective vaccination that travelers can get before going to areas where the disease is common.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.