Yellow fever

Yellow fever

• Yellow fever is caused by a virus that is transmitted by the bite of an infected mosquito. The word “yellow” in the name refers to the jaundice that affects some patients. 
• Yellow fever is found in tropical areas of Africa and South America.
• There is no cure for yellow fever. Fortunately, the majority of infected patients improve and their symptoms disappear after 3 to 4 days. However, 15% of patients enter a second, more toxic, phase of the disease. About half of the patients who enter the second phase die within 10 to 14 days, the rest recover. 
• Vaccination is the most important preventive measure against yellow fever.

People (older than 9 months of age) should only be vaccinated if they are at risk of exposure to yellow fever virus or require proof of vaccination for country entry. A single dose of vaccine is effective in providing protection from yellow fever.