Yellow fever

Will you need vaccination and certification for entry?

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Why is yellow fever important?

Yellow fever is a very dangerous and frequently fatal infection. It is caused by a virus that resides in primate carriers, humans and monkeys, and is occasionally transmitted to susceptible humans by mosquito bites. This disease was once present in the United States and caused outbreaks in New Orleans, Louisiana and Memphis, Tennessee that are among the worst disease-related disasters in our nation's history. Traditionally, the disease has been controlled by eliminating mosquitoes, an intervention derived from the pioneering work of Walter Reed at the beginning of the last century. However, we now have an effective yellow fever vaccine, and many developing countries plagued with this infection have successful vaccination programs to control its spread.

Yellow fever in travelers: Yellow fever is extremely rare in travelers to endemic countries. There are at least two major reasons for its rarity:

Vaccine Requirements:

Most countries that have yellow fever cases require proof of immunization at entry, but some do not. For example, Brazil and Colombia have areas of yellow fever transmission but do not require evidence of immunization for entry. Conversely, many countries (particularly tropical countries in Southern Asia) necessarily correlate with any real risk of exposure to the disease.

Because of the fear of this disease, yellow fever vaccine is currently the only infectious disease for which international entry requirements exist. The standard certification of immunization for U.S. travelers is the World Health Organization (WHO) Immunization Record. These cards, yellow fever vaccine, and the authority to certify immunization are available only through certified travel clinics (such as ours) or public health departments.

Do you need yellow fever vaccine?

The areas of the world where there is a risk of yellow fever are shown on the map below. Note: As explained above, this map does not list all of the countries that may require yellow fever vaccine for entry. For a detailed list of those countries, see the CDC web site at:

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