Yellow Fever: A Comprehensive Guide
Yellow fever is a viral haemorrhagic disease transmitted by infected mosquitoes, primarily in tropical regions of Africa and South America. It can cause mild flu-like symptoms or progress to severe liver damage, internal bleeding, and death. There is no specific cure, but vaccination, vector control, and supportive care are key in preventing severe illness and outbreaks.
What is Yellow Fever?
Yellow fever is an acute viral infection caused by the yellow fever virus (YFV), a member of the Flavivirus family. The virus is transmitted through the bite of infected mosquitoes, particularly the Aedes and Haemagogus species.
The name “yellow fever” comes from one of its severe symptoms: jaundice, a yellowing of the skin and eyes due to liver failure. In severe cases, it can lead to multiple organ failure, internal bleeding, and death.
Despite being preventable with a highly effective vaccine, yellow fever remains a significant public health concern in endemic areas.
Signs and Symptoms of Yellow Fever
Yellow fever has an incubation period of 3-6 days, after which symptoms appear. The disease progresses in two phases:
1. Acute Phase (Mild Symptoms):
- Fever and chills
- Headache and muscle pain (especially in the back)
- Nausea and Vomiting
- Loss of Appetite
- Fatigue and weakness
Most patients recover in 3-4 days. However, about 15% enter a toxic phase with severe complications.
2. Toxic Phase (Severe Yellow Fever – Life-Threatening):
- High fever returns
- Jaundice (yellowing of skin and eyes due to liver damage)
- Severe abdominal pain and vomiting (sometimes with blood)
- Bleeding (haemorrhages) – From the mouth, nose, eyes, and gastrointestinal tract
- Kidney and liver failure
- Shock, seizures, and coma
Mortality Rate: 30-60% of severe cases lead to death within 7-10 days.
Prevention of Yellow Fever
Preventing Yellow Fever involves a combination of vaccination, and good mosquito control.
1. Yellow Fever Vaccination
The best prevention against yellow fever is vaccination.
- Single-dose yellow fever vaccine provides lifelong immunity.
- Highly effective – Over 99% protection within 10 days of vaccination.
- Required for travellers visiting yellow fever-endemic countries.
Many countries require a Yellow Fever Vaccination Certificate (ICVP) for entry.
Yellow Fever Vaccination: Who Needs It?
- All travellers over 9 months of age visiting yellow fever-endemic regions should get vaccinated.
- Required for entry into certain countries in Africa and South America.
- Booster doses are no longer needed, as one dose gives lifelong immunity.
Who Should NOT Get Vaccinated?
- Infants under 6 months
- People with severe egg allergies
- Individuals with weakened immune systems (HIV, cancer patients)
- Pregnant women (unless traveling to high-risk areas)
Consult a doctor if you have medical conditions or a weakened immune system before getting vaccinated.
2. Mosquito Bite Prevention
- Use insect repellents with DEET or Picaridin.
- Wear long-sleeved clothing and trousers.
- Use mosquito nets and screens indoors.
- Stay in air-conditioned or well-screened accommodations.
- Avoid outdoor activities at dusk and dawn when mosquitoes are most active.
3. Mosquito Control Measures
- Eliminate standing water (breeding grounds for mosquitoes).
- Use insecticides and larvicides in high-risk areas.
- Community-wide mosquito control reduces transmission.
Regions Where Yellow Fever is Endemic
Yellow fever is endemic in:
- Africa – Angola, Democratic Republic of the Congo, Nigeria, Ghana, Sudan, Uganda, Ethiopia
- South America – Brazil, Colombia, Venezuela, Peru, Bolivia, Paraguay
Travellers visiting these areas must get vaccinated and carry a Yellow Fever Certificate.
Complications of Yellow Fever
Yellow fever can cause serious long-term complications, including:
- Liver and kidney failure
- Internal bleeding and haemorrhagic shock
- Heart rhythm disturbances
- Brain inflammation (encephalopathy)
- Death (if untreated in severe cases)
Survivors of severe yellow fever may experience weakness, fatigue, and liver complications for months after recovery.
Why Vaccinate at Trio Pharmacy's Travel & Vaccination Clinic in Shepperton?
If you’re planning to travel to an endemic region or want to protect yourself against yellow fever, Trio Pharmacy’s Travel & Vaccination Clinic in Shepperton is your trusted destination.
- Expert Guidance: Our trained healthcare professionals provide personalised advice tailored to your needs.
- Convenient Appointments: Flexible booking options to suit your schedule.
- Comprehensive Care: We ensure you receive the most up-to-date vaccinations and travel health information.