Introduction
Yellow fever is a serious viral infection transmitted by mosquitoes, primarily in parts of Africa and South America. The disease gets its name from the jaundice (yellowing of the skin and eyes) that can occur in severe cases. While many infections are mild, yellow fever can lead to life-threatening complications. Vaccination and mosquito bite prevention are the most effective ways to protect against this disease, especially for travelers to endemic regions.
Causes
Yellow fever is caused by the yellow fever virus, a flavivirus transmitted to humans through the bite of infected mosquitoes, mainly the Aedes and Haemagogus species. The virus is not spread from person to person.
Symptoms
Symptoms usually develop 3 to 6 days after being bitten by an infected mosquito and can range from mild to severe:
- Mild Phase:
- Fever
- Chills
- Headache
- Back pain
- Muscle aches
- Loss of appetite
- Nausea or vomiting
- Toxic Phase (Severe Cases):
- Recurrence of high fever
- Jaundice (yellowing of the skin and eyes)
- Abdominal pain
- Vomiting (sometimes with blood)
- Bleeding from the nose, mouth, eyes, or stomach
- Organ failure (especially liver and kidneys)
- Shock
Most people recover after the initial phase, but about 15% progress to the toxic phase, which can be fatal.
When to Seek Medical Attention
Seek immediate medical care if you develop symptoms of yellow fever after traveling to or living in an area where the disease is present, especially if you experience jaundice, bleeding, or severe abdominal pain.
Diagnosis
Diagnosis is based on:
- Medical History: Recent travel to endemic areas and symptom review.
- Laboratory Tests: Blood tests to detect the yellow fever virus or antibodies.
Treatment Options
There is no specific antiviral treatment for yellow fever. Management focuses on supportive care:
- Hospitalization: For severe cases, to monitor and support organ function.
- Supportive Care: Includes fluids, pain relief, and treatment of complications such as bleeding or organ failure.
- Avoid Certain Medications: Such as aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs), which can increase the risk of bleeding.
Prevention
Prevention is the best defense against yellow fever:
- Vaccination: The yellow fever vaccine is highly effective and recommended for people traveling to or living in endemic areas. Some countries require proof of vaccination for entry.
- Mosquito Bite Prevention: Use insect repellent, wear long-sleeved clothing, and stay in accommodations with screened windows or air conditioning.
- Eliminate Mosquito Breeding Sites: Remove standing water around homes and communities.
Takeaway
Yellow fever is a potentially deadly mosquito-borne disease. Vaccination and mosquito bite prevention are essential, especially for travelers to affected regions. If you develop symptoms after visiting an endemic area, seek medical care immediately.