Which of the following diseases can West Nile Virus cause?

West Nile Virus is primarily known for causing encephalitis, which is an inflammation of the brain. When a person is infected with West Nile Virus, especially severe cases can lead to neurological complications, including encephalitis or meningitis. This is a critical point of public health concern as it highlights the potential severity of infections spread by mosquitoes, the primary vectors of the virus.

The other listed diseases—malaria, yellow fever, and Lyme disease—are caused by different pathogens and are transmitted by different types of vectors. Malaria is caused by Plasmodium parasites transmitted by Anopheles mosquitoes, while yellow fever is caused by a virus and also transmitted by mosquitoes, specifically Aedes aegypti. Lyme disease is caused by a bacterium, Borrelia burgdorferi, and is spread by ticks, not mosquitoes. Understanding these distinctions helps clarify why only encephalitis is associated with West Nile Virus.