The first recorded epidemics were in Israel between 1951-54 and again in 1957. In 1996, the virus infected people in Romania, the Czech Republic, and Italy. West Nile encephalitis is an infection of the brain caused by West Nile virus. Encephalitis is an inflammation of the brain which can be caused by viruses and bacteria, including viruses transmitted by mosquitoes. The Centers for Disease Control says that most individuals infected by West Nile virus do not become seriously ill, the virus produces flu-like symptoms , high fever , headache , backache , fatigue , and nausea .
Most people recover from the infection within two weeks.
However it can be fatal, especially for the elderly. It is closely related to the St. Louis encephalitis virus already found in the United States. A bite from a mosquito infected with West Nile virus may transmit the infection. After an incubation period of 1 to 2 weeks, infected female mosquitoe s can then transmit West Nile virus to humans and animals while biting. The mosquitoes and their bites do not differ from the usual bites experienced from uninfected mosquitoes.