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What is it and how is it spread?

Yellow fever is a viral infection spread between monkeys and humans by the bite of an infected mosquito.1,2 It is found in two so-called yellow fever zones–in tropical parts of sub-Saharan Africa and South America. Worldwide, around 200,000 cases of yellow fever are thought to occur every year, mostly in Africa, leading to about 30,000 deaths.2

Who is at risk?

The risk to travellers from yellow fever is very low, less than 20 cases have been reported since the 1970s. You are at higher risk of infection if you stay in the affected area for longer, travel during the late rainy season to early dry season, or take part in activities that might increase the chances of being bitten by mosquitoes during the day.2

What are the symptoms?

Early symptoms of yellow fever appear around 3–6 days after the mosquito bite and include muscle pain, a high temperature, headache, loss of appetite, nausea (feeling sick) and vomiting. Many people make a gradual recovery 3–4 days after symptoms begin.1,2

In a small number of cases, within 24 hours of an apparent recovery, the disease can get worse. Symptoms may include bleeding from the mouth, eyes, ears and stomach, severe yellowing of the skin and eyes and major organ damage. Up to half of the people who develop this form of the disease do not survive.2

How can it be prevented?

If you are visiting areas affected by yellow fever you should make every effort to avoid mosquito bites. As the mosquito that carries yellow fever usually feeds during daylight hours, you should wear long clothing and use insect repellent throughout the day.1

Depending on your destination, you may require a certificate to show you have received a vaccine against yellow fever. Speak to your Healthcare Professional for further information once you have decided which country/countries you are going to.2

How can it be treated?

There is no specific treatment for the yellow fever virus.1

Where can I get further information?

If you have any questions or concerns about exposure to yellow fever, please speak to your doctor or a travel health practitioner for more information.

Make sure you contact your GP or travel health practitioner in plenty of time before you travel to discuss the ways you can help to keep yourself healthy whilst away. You should try and contact them at least 4–6 weeks before your trip.

After your trip, you should contact your GP if you develop a fever or notice any other unusual symptoms.

  1. Fit For Travel. Yellow Fever. Available at: Accessed August 2017.
  2. Travel Health Pro. Yellow Fever. Available at: Accessed August 2017.

Date of preparation: November 2017