Yellow Fever Yellow fever kills up to sixty per cent of those it attacks. It is a viral illness for which there is no cure, but there is an effective vaccine which will prevent it. The yellow fever virus continuously lurks in the background in the forests and jungles of Africa, Central and South America. Wild monkey populations act as a natural reservoir of virus in these tropical regions. The intermediary between man and monkey is a mosquito.
Mosquitoes acquire the virus through feeding on the blood of infected monkeys.
Should such an infected mosquito's next feed come from biting a human, that unfortunate person will most likely become a yellow fever victim. The illness develops within six days of being bitten by an infected mosquito, and the onset is usually sudden. A fever develops, with headache, body pains, and often nausea. The fever may then remit briefly, only to return as the sufferer's condition deteriorates. As the liver begins to reel under the virus' onslaught, a form of jaundice develops, with the victim turning yellow.