Mosquitoes become infected when they feed on a bird carrying the virus in its blood. After 10 to 14 days, the virus can be transmitted to another bird, person, or other animal that the mosquito bites. While taking a blood meal, the mosquito injects the virus, contained in its saliva, into the bird, animal or person. The virus then replicates and may cause illness. Although humans and some other animals may get sick when infected with West Nile Virus, it is thought that they usually do not develop enough virus in the bloodstream to infect mosquitoes. For this reason, humans and animals such as horses are referred to as incidental hosts. The principal transmission cycle of West Nile Virus involves several species of mosquitoes and various species of birds. WEST NILE VIRUS IS NOT SPREAD FROM PERSON TO PERSON. There is also no evidence that a person can get the virus from handling live or dead infected birds. However, persons should avoid contact with any dead animal because they can carry other diseases; use disposable gloves and/or plastic bags over your hands. Place the animal in two sealed plastic bags. The main role that people play in contributing to the continuing cycle of West Nile Virus is by maintaining environments (especially standing water) in which mosquitoes can lay eggs.