What is yellow fever?
Yellow fever is a potentially fatal viral infection, transmitted by mosquitoes in tropical regions. It has both an urban cycle and a jungle cycle that relies on monkeys as carriers (‘sylvatic cycle’). In mild cases the symptoms are similar to influenza, but serious cases develop a high temperature and may have a series of after effects, such as internal bleeding, kidney failure and meningitis. A classic feature of yellow fever is hepatitis, which is the reason for the yellow colouring of the skin (jaundice) and the name of the disease. Yellow fever can cause sudden epidemics, with a mortality rate of almost 50 per cent. Although a safe, efficient vaccine has been available for the last 60 years, epidemics still occur, constituting a health risk in tropical regions. The disease is covered by the International Health Regulations, which are taken very seriously by authorities everywhere. Therefore, the vaccine has to be administered by clinics registered as Yellow Fever Centres.
