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What Causes Yellow Fever and How Do You Catch It?

causes of yellow fever and how it spreads to humans

Yellow fever is a serious illness caused by a virus that spreads through mosquito bites. It mainly affects people living in or travelling to parts of Africa and South America. Though rare in the UK, it can still be a concern for anyone planning to visit these areas.

Let’s break down what yellow fever is, how it spreads, and what you can do to protect yourself.

What Is Yellow Fever?

Yellow fever is a mosquito-borne disease, which means it is passed to humans through the bite of an infected mosquito—most commonly the Aedes aegypti species. Once infected, a person can experience a range of symptoms, from mild flu-like signs to severe liver damage, bleeding, and in some cases, death.

Yellow Fever Causes and Transmission

The yellow fever virus is the root cause of this illness. It is found in the blood of infected people and animals, especially monkeys. A mosquito becomes infected after biting someone who has the virus. When it bites another person, it can pass the virus on.

This means yellow fever transmission depends entirely on mosquitoes. It doesn’t spread from person to person directly—only through mosquito bites.

Travellers to parts of Africa, South America, and Central America are most at risk, particularly in areas where vaccination is not common and mosquito control is weak.

What are the Common Symptoms of Yellow Fever?

Yellow fever symptoms often begin 3 to 6 days after a person is bitten by an infected mosquito. The illness has two stages. The majority of people recover after the first stage, but about 15% go on to develop the more serious toxic stage.

  1. Initial (Acute) Stage:
    • Fever
    • Headache
    • Muscle pain (especially in the back and knees)
    • Nausea or vomiting
    • Loss of appetite
    • Dizziness
  2. Toxic Stage (in some cases):
    • Yellowing of the skin and eyes (jaundice)
    • Abdominal pain
    • Bleeding from the mouth, nose, or eyes
    • Liver and kidney failure

Is There a Cure?

Unfortunately, there is no specific treatment to cure yellow fever. Doctors can only help manage the symptoms, like giving fluids, managing pain and fever, and treating any secondary infections. That’s why prevention is so important.

How to Prevent Yellow Fever?

The most effective way to protect yourself is through the yellow fever vaccine. This single shot offers lifelong protection in most people and is usually required if you’re travelling to a country where the disease is present. Many countries won’t even let you in without proof of vaccination.

Aside from vaccination, yellow fever prevention also includes:

  • Using insect repellent on exposed skin
  • Wearing long sleeves and trousers, especially at dawn and dusk
  • Sleeping under mosquito nets
  • Staying in places with air conditioning or screened windows

These steps help reduce the risk of mosquito bites and, in turn, lower your chances of getting any mosquito-borne diseases.

Who Needs the Yellow Fever Vaccine?

You should consider getting the vaccine if:

  • You’re travelling to or through a country with yellow fever
  • You’re staying in rural or jungle areas where mosquitoes are more active
  • You’re going to a country that requires proof of yellow fever vaccination for entry

The vaccine is not suitable for everyone, such as babies under 6 months, people with weakened immune systems, and those with severe allergies to eggs. Speak to a pharmacist or travel health expert to check if it’s right for you.

Protect Your Travels with Confidence

Yellow fever may sound like something far from home, but if you’re travelling to the affected areas, it’s a real risk. Thankfully, it’s one of the few mosquito-borne diseases that can be prevented with a single vaccine. Don’t take chances—prepare early and stay protected. Planning a trip abroad? Don’t let yellow fever ruin it. Book your yellow fever vaccination at Touchwood Pharmacy today and travel safely with peace of mind. Our qualified pharmacists are here to guide you and provide the right protection for your journey. It’s quick, reliable, and one step towards a worry-free trip!