Yellow fever

Yellow Fever: Causes, Symptoms, Transmission, Prevention, and Immunization

Causes: Yellow fever is caused by a virus primarily found in rural areas of Africa and South America.

Symptoms: While yellow fever often occurs without symptoms, those that do manifest include fever attacks, shivering, extreme fatigue, headaches, backaches, and vomiting. The onset is sudden, followed by a temporary remission 2 to 5 days later. Subsequently, renal impairment and hemorrhage may occur, leading to jaundice. The disease carries a 20 to 30 percent mortality rate.

Transmission: Transmitted by the Aedes mosquito, which can bite at any time, especially in shady areas or indoors. Forest areas with monkeys acting as virus reservoirs also contribute to transmission. The incubation period ranges from 3 to 6 days, and infection provides permanent immunity.

Prevention: Precautions against mosquitoes are crucial: use insect repellent, bed netting, and wear light-colored, long-sleeved clothing. The risk of contracting yellow fever during travel is relatively low, thanks to effective international sanitary measures preventing its spread.

Immunization: Vaccination is essential for those traveling to endemic areas. The vaccine is highly effective and provides sustained protection. It can be administered to individuals aged 9 months and older in a single shot. While generally well-tolerated, about 10 percent of individuals may experience weakness, stomach upset, and headaches 5 to 10 days post-vaccination. Many countries mandate yellow fever vaccination for incoming travelers. Ensure the vaccine is WHO-approved, and visit an authorized travel clinic for administration.

For additional details, refer to “Essential Information for a Safe Trip.”