Yellow Fever is a viral infection spread by the bite of an infected mosquito, often the Aedes egyptii. It exists in the tropical areas of South America and Africa, and infects non-human primates as well as humans. For this reason there is a risk of getting it in the jungles of these regions, but one can also get it if bitten by a mosquito which has fed on a Yellow Fever victim who has returned to the city (aggressive control measures have practically eliminated this as an urban problem). Because your odds of dying with this disease may be as high as 50%, it is very important to get the vaccination if traveling to at-risk areas.
Yellow Fever gets its name because after the initial phase of illness (fever, aches, nausea) subsides, a phase of liver inflammation sets in - marked by jaundice (you turn yellow) and hemorrhage (bleeding).
- This is the only vaccine generally required for travel other than meningitis vaccine required for travel to Mecca during the Hajj pilgrimage.
- It must be given by a licensed Yellow Fever vaccination clinic, and a "Yellow Card" - an International Certificate of Vaccination - will be given. This must be taken by the traveler as proof of vaccination - nothing else will suffice.
- You may need vaccination even if you will not be at risk. For example - neither Brazil nor Peru require Yellow Fever vaccination for travel to those countries - if you are going to Rio de Janeiro or Lima you will not be at risk for Yellow Fever. However - if you attempt to go from Brazil to Peru (or vice versa, or to any other country which has the possibility of having Yellow Fever - even some Asian Countries where is does not now exist) - you will not be allowed to enter. The Peruvian authorities do not know whether you went into the Amazon Basin while in Brazil. The vaccine requirement is not to protect you from getting the disease as much as to prevent anyone from bringing it into the country.
- The vaccine must be obtained ten days prior to possible
exposure, and is good for ten years.