West Nile virus (WNV) is a mosquito-borne illness. It is most commonly spread to people by the bite of an infected mosquito. Most people infected with WNV will have no symptoms. About 1 in 5 people infected will develop a fever with other symptoms. Less than 1 percent of those infected will develop a serious, sometimes fatal, neurologic illness. There are no vaccines to prevent or medications to treat WNV in people. Humans and horses both exhibit disease symptoms from the virus, and symptoms rarely occur in other animals. The virus can cause severe disease and death in horses. Vaccines are available for use in horses but not yet available for people. Birds are the natural hosts of West Nile virus. If you would like to find out more and receive a second opinion regarding your diagnosis and treatment, please contact us at secondopinions.com, for your peace of mind.