Yellow Fever

What is yellow fever?

Yellow fever is a disease caused by a virus that is spread through mosquito bites. Symptoms take 3–6 days to develop and include fever, chills, headache, backache, and muscle aches. About 15% of people who get yellow fever develop serious illness that can lead to bleeding, shock, organ failure, and sometimes death. Get the latest updates and resources on yellow fever for travelers.

Who is at risk?

You should receive a yellow card called the International Certificate of Vaccination or Prophylaxis (ICVP) to prove that you have had yellow fever vaccine. Some countries require all travelers to show proof of yellow fever vaccination before they can enter the country. Other countries require proof of vaccination only if travelers have been in a risk area, so if you are visiting multiple countries, the order of travel may be important. Proof of vaccination is not valid until 10 days after you get the vaccine, so plan to get the vaccine early if you need it.

Travelers to certain parts of South America and Africa are at risk for yellow fever. See the box below for specific information about the country where you are traveling.

What can travelers do to prevent yellow fever?

Travelers can protect themselves from yellow fever by getting yellow fever vaccine and preventing mosquito bites.

Get yellow fever vaccine if recommended or if required:

Visit a yellow fever vaccination (travel) clinic and ask for a yellow fever vaccine.
- You should receive this vaccine at least 10 days before your trip.
- After receiving the vaccine, you will receive a signed and stamped International Certificate of Vaccination or Prophylaxis (ICVP, sometimes called the “yellow card”), which you must bring with you on your trip.
- The vaccine lasts for life for most people, but a booster after 10 years is recommended for certain people. See Yellow Fever Vaccine Booster Doses for more information.

Note: CDC’s recommendation is different from the country’s requirement. A vaccine recommendation is designed to keep you from getting yellow fever; a vaccine requirement is the country’s attempt to keep travelers from bringing the yellow fever virus into the country. CDC does not have any control over other countries’ vaccine requirements or how they are enforced.

Prevent mosquito bites:

In rare cases, the yellow fever vaccine can have serious and sometimes fatal side effects. People older than 60 years and people with weakened immune systems might be at higher risk of developing these side effects. Also, there are special concerns for pregnant and nursing women. Talk to your doctor about whether you should get the vaccine.

Cover exposed skin by wearing long-sleeved shirts, long pants, and hats.
Use an appropriate insect repellent as directed.
Higher percentages of active ingredient provide longer protection. Use products with the following active ingredients:
- DEET (Products containing DEET include Off!, Cutter, Sawyer, and Ultrathon)
- Picaridin (also known as KBR 3023, Bayrepel, and icaridin products containing picaridin include Cutter Advanced, Skin So Soft Bug Guard Plus, and Autan [outside the US])
- Oil of lemon eucalyptus (OLE) or PMD (Products containing OLE include Repel and Off! Botanicals)
- IR3535 (Products containing IR3535 include Skin So Soft Bug Guard Plus Expedition and SkinSmart)
Always follow product directions and reapply as directed:
- If you are also using sunscreen, apply sunscreen first and insect repellent second.
- Follow package directions when applying repellent on children. Avoid applying repellent to their hands, eyes, and mouth.
Use permethrin-treated clothing and gear (such as boots, pants, socks, and tents). You can buy pre-treated clothing and gear or treat them yourself:
- Treated clothing remains protective after multiple washings. See the product information to find out how long the protection will last.
- If treating items yourself, follow the product instructions carefully.
- Do not use permethrin directly on skin.
Stay and sleep in screened or air conditioned rooms.
Use a bed net if the area where you are sleeping is exposed to the outdoors.

If you are bitten by mosquitoes:

Avoid scratching mosquito bites.
Apply hydrocortisone cream or calamine lotion to reduce itching.

If you feel sick and think you may have yellow fever:

Talk to your doctor or nurse if you feel seriously ill, especially if you have a fever.
- Tell them about your travel.
- For more information about medical care abroad, see Getting Health Care Abroad and a list of International Joint Commission-accredited facilities.
Use acetaminophen. Do not take pain relievers that contain aspirin and ibuprofen (Advil), it may lead to a greater tendency to bleed.
Get lots of rest, and drink plenty of liquids.
Avoid spreading the disease by preventing more mosquito bites.