Key points
- There is no specific treatment for West Nile virus (WNV) disease; clinical management is supportive.
- No WNV vaccines are licensed for use in humans.
- Prevention of WNV disease depends on community-level mosquito control programs, personal protective measures, and screening of blood and organ donors.
- Patients with WNV disease should not donate blood for 4 months after their illness.
Treatment
There is no specific treatment for WNV disease; clinical management is supportive. Patients with severe meningeal symptoms often require pain control for headaches and antiemetic therapy and rehydration for associated nausea and vomiting.
Patients with encephalitis require close monitoring for the development of elevated intracranial pressure and seizures. Patients with encephalitis or poliomyelitis should be monitored for inability to protect their airway. Acute neuromuscular respiratory failure may develop rapidly, and prolonged ventilatory support may be required.
Various drugs have been evaluated or empirically used for WNV disease. However, none has shown specific benefit to date.
Prevention
No WNV vaccines are licensed for use in humans. In the absence of a vaccine, prevention of WNV disease depends on community-level mosquito control programs to reduce vector densities, personal protective measures to decrease exposure to infected mosquitoes, and screening of blood and organ donors. Personal protective measures include use of mosquito repellents, wearing long-sleeved shirts and long pants, and limiting outdoor exposure from dusk to dawn. Using air conditioning, installing window and door screens, and reducing mosquito breeding sites around the home, can further decrease the risk for WNV exposure. More information on personal protective measures can be found on the CDC Mosquitoes website.
Blood and some organ donations in the United States are screened for WNV infection; healthcare professionals should remain vigilant for the possible transmission of WNV through blood transfusion or organ transplantation. Any suspected WNV infections temporally associated with blood transfusion or organ transplantation should be reported promptly to the appropriate state or local health department. People with confirmed WNV infections should not donate blood for 120 days (4 months) after their illness.
- Kaiser JA, Barrett ADT. Twenty years of progress toward West Nile virus vaccine development. Viruses. 2019;11(9):823. doi: 10.3390/v110908231
- Gould CV, Staples JE, Huang CY-H, Brault AC, Nett RJ. Combating West Nile virus disease – time to revisit vaccination. N Engl J Med. 2023;388(18):1633-1636. doi: 10.1056/NEJMp2301816
- Soto RA, McDonald E, Annambhotla P, Velez JO, Laven J, Panella AJ, et al. West Nile virus transmission by solid organ transplantation and considerations for organ donor screening practices, United States. Emerg Infect Dis. 2022;28(2):403-406. doi:10.3201/eid2802.211697
- Nasci RS, Mutebi JP. Reducing West Nile virus risk through vector management. J Med Entomol. 2019;56(6):1516-1521. doi: 10.1093/jme/tjz083