Yellow Fever

What is yellow fever?

Yellow fever is a viral infection common in South America and Africa. Severity ranges from mild “flu-like” symptoms to a life-threatening illness. Recovery is expected for most patients. Importantly, it is a preventable disease. Travelers to Africa and South America have 2 important methods to prevent this disease – vaccination and mosquito avoidance. Since there is no treatment, prevention is the key strategy.

How is yellow fever transmitted?

Yellow fever is transmitted to humans through the bite of an infected mosquito. You cannot catch yellow fever from an infected person.

What are the symptoms?

Infected individuals suffer fever, chills, headache, muscle aches, nausea, and fatigue. Yellow fever gets its name as some people with severe infections develop jaundice, when their eyes and skin turn yellow. The symptoms of yellow fever are non-specific, meaning that they can occur in many other diseases also. Many people with yellow fever may have only a mild illness that can be mistaken for a simple flu. Some people may have no symptoms at all. Yellow fever can progress to a severe illness with life threatening complications. After a person recovers, they are generally immune to the disease.

How is yellow fever diagnosed?

Physicians suspect yellow fever when an individual has compatible symptoms and was in an area with known yellow fever activity. There are blood tests available, but these may not be available in the developing world, and results can take up to two weeks to be completed.

Viral diseases generally are not treated with specific medications like antibiotics. Medications can be given to relieve symptoms such as fever and muscle aches. The disease needs to run its course.

Can yellow fever be prevented?

Yes. The most effective strategy is vaccination. Yellow fever vaccine is strongly recommended for travelers who will be in parts of the world where this infection is common. Unlike other vaccines, yellow fever vaccination can only be administered by medical practitioners who have been certified by their state health departments. Many countries require an International Certificate of Vaccination as proof of vaccination before entry. Since no vaccine is 100% effective, travelers need to take precautions to avoid mosquito bites. Insect repellents and proper clothing treated with repellants are important strategies to minimize risk. Yellow fever-carrying mosquitoes feed during daylight hours, so travelers should plan and prepare accordingly.