West Nile Virus (WNV) is an arthropod-borne virus spread by mosquitoes. West Nile Virus has its peak during warmer seasons, with an incubation period of two to fourteen days. In most cases, symptoms are minimal and resolve on their own. Mosquitoes, humans, and birds infected with West Nile Virus can be found in all 48 continental United States. Other modes of transmission include blood transfusions and organ transplants.
Typically, humans infected with West Nile are asymptomatic. However, 1 in 5 people develop febrile illness, characterized by body aches, headaches, vomiting, joint pain, diarrhea, or rash. Less than 1% of those infected contract neurological complications such as encephalitis or meningitis. Those at greatest risk for developing a neurological illness from West Nile Virus include people over 60, especially those with cancer, diabetes, hypertension, and kidney disease. Recovery, while possible, can take weeks or months. 10% of people who develop a neurological illness from West Nile Virus will die.
Symptoms of West Nile Virus can be relieved by over-the-counter pain relievers. Treatment of WNV includes mostly supportive care with rest, fluids, and antipyretics. Much of the prevention of the virus relies on local mosquito-control systems and personal protection, including bug spray and long-sleeved shirts and pants.
There are currently no available vaccines for West Nile Virus. However, there are several candidates in development.