What is Yellow Fever?

Yellow fever is a viral infection spread by mosquitoes. It is most commonly found in tropical and subtropical areas of Africa and South America. A person contracts the virus when they are bitten by an infected mosquito.

People who travel are at risk of contracting yellow fever if they visit areas where the disease is more common. However, it is a rare cause of illness for U.S. travelers.

There is no cure for yellow fever, but it is a vaccine-preventable disease.

What are the symptoms and complications of yellow fever?

Most people who contract the yellow fever virus will either have mild symptoms or no symptoms at all and recover fine. For people who develop symptoms, it usually takes three to six days from the time they are infected until they start to feel sick.

Symptoms of yellow fever include:

  • Sudden onset of fever
  • Chills
  • Severe headache
  • Back pain and body aches
  • Nausea or vomiting
  • Fatigue and weakness

Most people start to feel better after about a week. For some people, the fatigue and weakness may last several weeks or months.

About one in seven people who have initial symptoms will recover for a short period of time and then experience more severe symptoms.

Severe symptoms of yellow fever include:

  • High fever
  • Jaundice (yellowing of the skin)
  • Bleeding
  • Shock
  • Organ failure

About 30 to 60 percent of people who experience severe symptoms of yellow fever will die from the disease.

The best way to protect yourself from yellow fever is by preventing mosquito bites and getting vaccinated before traveling.

Who should get the yellow fever vaccine?

A yellow fever vaccine has been available for more than 80 years. It is a live, weakened form of the virus given as a single shot. For most people, a single dose of the vaccine will provide protection for life.

The yellow fever vaccine is recommended for people nine months of age and older and who are traveling to or living in high-risk areas. A booster of the vaccine may be recommended if it has been 10 years or more since the original vaccination.

The vaccine may also be recommended for entry into certain countries. Visit the CDC Travelers’ Health Page for vaccination requirements.

Talk to your doctor about the best strategy for vaccination.

Is the yellow fever vaccine safe?

The yellow fever vaccine is safe and effective. A single dose of the vaccine can provide protection from yellow fever for a person’s entire life.