Yellow Fever is a serious and sometimes fatal viral disease that is spread by mosquitoes in tropical parts of Africa and South America. It occurs in both jungle and urban environments and is particularly common in the rainy season.
Countries at risk
Nearly all affected countries require proof of yellow fever vaccination in the form of an International Certificate of Vaccination before they allow a traveller to enter. Failure to provide a valid certificate can lead to a traveller being quarantined, immunised or denied entry.
Signs and symptoms
The first phase of Yellow Fever includes symptoms such as fever, muscle pain, headache, shivers, loss of appetite, nausea and vomiting. After three to four days most patients improve and their symptoms disappear. However, within 24 hours of apparent recovery, some patients progress to a more serious stage of the illness involving jaundice, haemorrhagic fever and deterioration of kidney function. Some patients that develop this form of the disease die within 7-10 days after the onset.
Risk of acquiring yellow fever is determined by immunisation status, travel destination and its intensity level of yellow fever transmission, season of travel, duration of travel and activities allowing exposure to mosquitoes.
Yellow Fever cannot be treated effectively, but is preventable by vaccination. Travellers to areas at risk may require a single dose injection of Stamaril.