Yellow fever in the Americas

Level 1 - Practise health precautions (more details)

Original publication date: April 22, 2025

Current situation

Yellow fever outbreaks are occurring in several countries within the Americas:

Brazil
Colombia
Peru

There may be an increased risk of yellow fever in these countries due to the current outbreaks. Yellow fever can be prevented by a vaccine. Getting vaccinated against yellow fever before you travel may be recommended depending on your itinerary, and proof of vaccination may be required.

About yellow fever

Yellow fever is caused by a virus that is spread to humans by the bites of infected mosquitoes.

Symptoms can take 3 to 6 days to appear, and may include:

fever
chills
headache
joint and muscle pain
back pain
nausea and vomiting
fatigue
dehydration
weakness

Most people recover after this stage, but about 15% of patients develop a more severe form of the disease, which can lead to jaundice (yellowing of the skin and whites of the eyes), organ failure, internal bleeding and shock. The case fatality rate of severe cases is 30-60%, and typically occurs within 10-14 days.

There is no specific treatment for yellow fever, only supportive care to help relieve symptoms. If you have had yellow fever once, you are likely protected against future infections.

Recommendations

Before your trip

Talk to a healthcare provider or visit a travel health clinic preferably about 6 weeks before your trip to get personalized health advice. Even if your travel date is coming up soon, it’s still worthwhile to make an appointment.

Vaccination is recommended for anyone 9 months of age or older travelling to any area with a known or potential risk for yellow fever, including certain regions of the Americas.

Verify the yellow fever vaccination recommendations and entry requirements for your destination on the health tab of your destination’s Travel Advice and Advisories page, under the ‘Pre-travel vaccines and medications’ section: Travel advice and advisories by destination

If recommended, get vaccinated at least 10 days before travelling. The vaccine takes 10 days to take effect.
Contact a Yellow Fever Vaccination Centre at least 6 weeks before you travel to make sure that they have yellow fever vaccine.
When you get vaccinated, you will be provided with written proof of yellow fever vaccination in the form of an International Certificate of Vaccination or Prophylaxis. The certificate is not valid until 10 days after the vaccine is administered. If vaccination is required for entry, you will need to travel with this certificate.

Sign up with the Registration of Canadians Abroad service to stay connected with the Government of Canada in case of an emergency abroad or an emergency at home.

Registration of Canadians Abroad

Learn more:
World Health Organization: Vaccination requirements and recommendations
Yellow Fever Vaccination Centres in Canada

During your trip

Protect yourself from mosquito bites. Mosquitoes that spread yellow fever typically bite during the daytime, particularly around sunrise and sunset.

To protect yourself from bites:

use an approved bug spray (insect repellent) on exposed skin
wear light-coloured, loose clothing made of tightly woven materials like nylon or polyester
wear socks and closed-toe shoes
sleep under mosquito netting if you’re outdoors or staying in places that aren’t fully enclosed

Visiting rural or jungle areas, or participating in outdoor activities such as camping, hiking, cycling or fieldwork may increase your exposure to mosquitoes.

Learn more:
Insect bite and pest prevention
Personal insect repellents

After your trip

If you develop symptoms similar to those of yellow fever when you are travelling or after you return, calla healthcare provider and notify them of your symptoms. Tell them where you have been travelling or living and about your activities while travelling.

Fever and other symptoms of yellow fever can be similar to many other infections, and you can’t always tell them apart without lab tests.

Learn more:
If you become sick or injured while travelling outside Canada or after your return