A dead crow infected with West Nile Virus was found in Arcadia on September 3, and is the first confirmed finding of the virus in Los Angeles County this year. Exposure to West Nile Virus is spread to humans from the vite of an infected mosquito. Biting a bird that carries the virus infects a mosquito. The San Gabriel Valley Mosquito and Vector Control District is encouraging the public to take precautions to reduce exposure to mosquitoes.