Yellow Fever

What is yellow fever?

Yellow fever is a rare viral disease caused by the bite of a mosquito. Many countries still require visitors to be vaccinated for it before entering.

Yellow fever is found mainly in certain areas of Africa and in South America. In South America, infections happen only every now and then. They are usually among forestry and agricultural workers. In Africa, infections happen mostly in the tropical areas of western and central Africa. But they also happen in cities and jungle areas.

What causes yellow fever?

Yellow fever is caused by a virus (flavivirus). The virus is passed on to people through the bite of a mosquito (Aedes aegypti).

What are the symptoms of yellow fever?

Each person may have slightly different symptoms. The following are the most common symptoms:

  • Fever
  • Flu-like symptoms, such as headache, vomiting, and backache
  • Bleeding of the gums
  • Bloody urine
  • Yellowing of the skin or eyes (jaundice)

Symptoms usually happen within 3 to 6 days after you are exposed to the virus. Symptoms may look like other health problems. Always see your healthcare provider for a diagnosis.

How is yellow fever diagnosed?

Your healthcare provider will ask about your past health and travel history for dates and exact locations. You will also need an exam. Blood tests can also help with a diagnosis.

How is yellow fever treated?

Your healthcare provider will figure out the best treatment for you based on:

  • How old you are
  • Your overall health and past health
  • How sick you are
  • How well you can handle specific medicines, procedures, or therapies
  • How long the condition is expected to last
  • Your opinion or preference

Treatment is aimed at controlling your symptoms. This includes rest and plenty of fluids. You may also need to take medicine to help relieve fever and aching. You should not take aspirin or nonsteroidal anti-inflammatory medicines (like ibuprofen or naproxen). These may raise the risk of bleeding.

You should protect yourself from mosquitoes during the illness. This may mean staying indoors or under a mosquito net. This will help keep you from passing the disease on to other people.

What are the complications of yellow fever?

Most people who get yellow fever do not have complications. They may not even know they have had the disease. Some people who get it may have some weakness and fatigue for a few months after symptoms go away. If severe disease happens, death is possible.

Can yellow fever be prevented?

A vaccine is available for yellow fever. The disease no longer happens in the U.S. But talk with your healthcare provider to see if you need the shot before visiting areas where yellow fever still exists. People who have had yellow fever develop lifelong immunity. As of June 2016, the World Health Organization recommends a one-time yellow fever vaccine, instead of a vaccine every 10 years.

When should I call my healthcare provider?

Call your healthcare provider right way if your symptoms get worse or you have new ones.

Key points about yellow fever

  • Yellow fever is a disease caused by a virus passed on through the bite of a daytime-biting mosquito.
  • Yellow fever happens only in certain areas of Africa and South America.
  • The disease causes flu-like symptoms, slow and weak pulse, bleeding of the gums, bloody urine, and yellow skin (jaundice).
  • Treatment is aimed at controlling the symptoms. It includes rest and plenty of fluids. You may also need to take medicine to help relieve fever and aching.
  • A vaccine is available to prevent yellow fever. You may need it before traveling to some tropical countries in Africa or South America.
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