West nile encephalitis is caused by a virus called West Nile. Bacterial infections and viruses that are transmitted by mosquitoes are some of the causes of encephalitis. This type of virus is an arbovirus that belongs to the family Flaviviridae and the genus Flavivirus.
Someone else can get infected from the mosquito bite that carries the virus, but the encephalitis itself is not spread by individuals.
Moreover, there is no evidence that a person could acquire the virus by touching infected birds, either alive or dead. However, it is still recommended that you avoid touching dead animals with your hands.