What Causes Yellow Fever and How Does It Spread? Causes, Transmission & Prevention in Ghana
Yellow fever is still a serious health threat in Ghana. Ghana is in the yellow fever endemic zone in Africa, and outbreaks are reported almost every year, especially during and after the rainy season.
At Citi Pharmacy Ltd., many customers ask: “Is yellow fever caused by dirty water? Can it spread from person to person?” Let’s clear the confusion.
What Causes Yellow Fever?
Yellow fever is NOT caused by bacteria, dirty water, or spiritual attack.
It is caused by the Yellow Fever Virus – a virus belonging to the Flavivirus family. The same family that causes dengue and Zika.
Once this virus enters your body, it attacks your liver, kidneys, and blood vessels. That’s why some people develop jaundice (yellow skin and eyes) – which gives the disease its name “yellow fever”.
You cannot get yellow fever by touching or hugging someone who has it. You can only get it through the bite of an infected mosquito.
How Does Yellow Fever Spread? 3 Transmission Cycles
The virus is spread only by infected mosquitoes. In Ghana and West Africa, there are 3 ways it spreads:
1. Jungle or Sylvatic Cycle (Monkey to Mosquito to Human)
This happens in forests in parts of Volta, Eastern, and Northern Ghana. Monkeys are the main reservoir. A forest mosquito (Aedes africanus) bites an infected monkey, then bites a farmer, hunter, or someone visiting the forest. This is how most outbreaks start in Ghana.
2. Intermediate or Savannah Cycle (The Most Common in Ghana)
This is the most common cycle in Ghana. It happens in villages near forests. Both monkeys and humans are involved. Semi-domestic mosquitoes that breed around homes (Aedes furcifer, Aedes luteocephalus) bite infected monkeys and then bite people. Small village outbreaks happen this way.
3. Urban Cycle (Human to Mosquito to Human)
This is the most dangerous and causes large outbreaks in cities like Accra, Kumasi, and Ho.
A person infected in the village travels to the city. A domestic mosquito – Aedes aegypti – the same mosquito that spreads malaria and dengue, bites that person. That mosquito then bites many other people in the same area, spreading it fast. This mosquito bites during the day and breeds in clean standing water in tyres, buckets, and open tanks around homes.
Key Point: Aedes aegypti bites mostly during the day, from morning to evening. Unlike malaria mosquitoes that bite at night, you need protection during the day too.
Who Is at Risk in Ghana?
Everyone in Ghana is at risk if not vaccinated, but risk is higher if you:
– Live or work near bushes, forests, or farms
– Have not received yellow fever vaccine
– Store water in open containers around your home
– Travel to rural areas without vaccination
– Are a child, as many children miss booster checks
Can Yellow Fever Spread from Person to Person?
No. You cannot get it from shaking hands, eating together, sexual contact, or through the air. It ONLY spreads through the bite of an infected mosquito. However, a mosquito can bite an infected person and then bite you.
How to Protect Yourself from Yellow Fever– Advice from Citi Pharmacy
1. Vaccination is the best protection. One dose gives you lifelong protection. It is available at Ghana Health Service centers and selected private facilities. Keep your yellow card safe.
2. Destroy mosquito breeding sites: Empty tyres, buckets, flower pots, and open water tanks weekly.
3. Use protection: Use insecticide-treated nets, mosquito repellents, and wear long sleeves when going to farms or forests, especially in the day.
4. Visit early: If you have sudden fever, headache, back pain, and yellowing of eyes within 3-6 days after a mosquito bite, visit a health facility immediately. Do not self-medicate.
At Citi Pharmacy Ltd., we provide mosquito repellents, education, and referral for yellow fever vaccination services at our partner facilities. Visit our branches in Ho – Dome, Housing Road.
Frequently Asked Questions (FAQs)
1. Can yellow fever be cured with antibiotics or herbal medicine?
No. Yellow fever is caused by a virus, so antibiotics do not work. There is no specific medicine that cures it. Treatment is supportive care in a hospital. Vaccination is the only effective prevention. Herbal mixtures cannot prevent or cure yellow fever – always seek proper medical care.
2. How long after a mosquito bite will I know I have yellow fever?
Symptoms usually appear 3 to 6 days after you are bitten by an infected mosquito. It starts with sudden fever, chills, severe headache, back pain, and body aches. In severe cases, yellowing of eyes, vomiting of blood, and bleeding may appear after a few days. If you notice this, go to the hospital immediately.
3. Does one yellow fever vaccine give lifelong protection in Ghana?
Yes. According to WHO and Ghana Health Service, one dose of yellow fever vaccine gives lifelong protection. You do not need a booster every 10 years as was previously advised. However, you must keep your yellow fever card (yellow card) safe as proof for travel and school admission.
4. Can I get yellow fever even if I am vaccinated?
It is very rare. The vaccine is about 99% effective within 30 days after vaccination. That is why vaccination is the best protection. If you were vaccinated more than 10 years ago and lost your card, speak to a health worker about verification before revaccination.
Medical Disclaimer: This article is for education only and does not replace professional medical advice. If you suspect yellow fever, visit the nearest hospital or contact Ghana Health Service immediately.
Reference Links
1. World Health Organization (WHO) – Yellow Fever Fact Sheet
2. Centers for Disease Control and Prevention (CDC) – Yellow Fever Transmission
3. Ghana Health Service – Disease Surveillance & Yellow Fever Control
4. WHO Afro – Yellow Fever in Ghana Situation Report
