Yellow Fever - Questions And Answers | Purple Turtle Skip to main content

Yellow fever is a serious, potentially deadly flu-like disease spread by mosquitoes. It’s characterised by a high fever and jaundice. Jaundice is yellowing of the skin and eyes, which is why this disease is called yellow fever.

The Flavivirus causes yellow fever, and it’s transmitted when an infected mosquito bites you. Mosquitoes become infected with the virus when they bite an infected human or monkey. The disease cannot be spread from one person to another.

Yellow fever develops quickly, with symptoms occurring three to six days after exposure. The initial symptoms of the infection are similar to those of the influenza virus. 

Acute Phase – This phase usually lasts for three to four days. Common symptoms include:

– headaches

– muscle aches and joint aches

– a fever and flushing

– a loss of appetite

– shivers and backaches

After the acute phase is over, symptoms will begin to go away. Many people recover from yellow fever at this stage, but some people will develop a more serious version of this condition.

Toxic Phase – The symptoms that you experienced in the acute phase may disappear for up to 24 hours. Then, those symptoms will return, along with new and more serious symptoms. These include:

– decreased urination

– abdominal pain and vomiting (sometimes with blood)

– heart rhythm problems and seizures

– delirium

– bleeding from the nose, mouth, and eyes

This phase of the disease is often fatal, but only 15 percent of people with yellow fever enter this phase.

See your doctor right away if you’ve been travelling recently and you experience flu-like symptoms. Your doctor will ask you about the symptoms you’ve been experiencing and if you’ve traveled recently.

If your doctor suspects that you have yellow fever, they’ll order a blood test. Your blood sample will be analysed for the presence of the virus or for the antibodies meant to fight the virus.

There’s no cure for yellow fever. Treatment involves managing symptoms and assisting your immune system in fighting off the infection by:

– getting enough fluids, possibly through your veins

– getting oxygen maintaining a healthy blood pressure

– getting blood transfusions having dialysis if you experience kidney failure

– getting treatment for other infections that may develop


The yellow fever virus is found in tropical and subtropical areas of Africa and South America.

Vaccination is the only way to prevent yellow fever. The vaccine for yellow fever is given as a single shot. It contains a live, weakened version of the virus that helps your body create immunity. The Centers for Disease Control (CDC) suggests that anyone who is 9 months through 59 years old and travelling to or living in an area where the risk of yellow fever is present should be vaccinated.

Groups of people who shouldn’t get the vaccine include:

– people who have severe allergies to eggs, chicken proteins, or gelatin

– infants younger than 6 months old

– people who have HIV, AIDS, or other conditions that compromise the immune system.

If you’re older than 60 and you’re considering travelling to an area that may have the virus, you should discuss vaccination with your doctor. If you’re travelling with an infant who is 6 to 8 months old or you’re a nursing mother, you should either postpone travel to these areas if possible or talk to your doctor about vaccination.

The vaccine is considered extremely safe. A single dose provides protection for at least 10 years. The side effects may include:

– a mild headache

– muscle pain

– fatigue

– a low-grade fever

After getting the vaccine, you should be given a stamped and signed “International Certificate of Vaccination or Prophylaxis” (yellow card). This certificate becomes valid 10 days after vaccination and is good for 10 years. You will need this card as proof of vaccination to enter certain countries. Travelers without proof of vaccination could be given the vaccine upon entry or detained for up to 6 days to make sure they are not infected.

Sleeping under a mosquito net may help prevent being bitten by an infected mosquito.

Covering your skin or using bug sprays containing DEET may also help prevent infection.

Insect repellent clothing and accessories are also a great protection from unwanted bites.

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