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Updated: May 29, 2026
07:23
Detection of Infectious Virus from Field-collected Mosquitoes by Vero Cell Culture Assay
Published on: June 9, 2011
West Nile virus: North American experience
1USGS National Wildlife Health Center, Madison, Wisconsin 53711, USA. ehofmeister@usgs.gov
Integrative Zoology
|September 14, 2011
Summary
West Nile virus, a mosquito-borne flavivirus, has spread across North America since 1999, impacting birds, horses, and humans. This review details its emergence, spread, and effects.
Area of Science:
- Veterinary Medicine
- Epidemiology
- Public Health
Background:
- West Nile virus (WNV) is a mosquito-vectored flavivirus first detected in North America in 1999.
- Prior to WNV, St. Louis encephalitis virus and Dengue virus were the primary mosquito-borne flaviviruses causing human illness in North America.
Purpose of the Study:
- To review the North American experience with mosquito-borne flaviviruses before WNV.
- To detail the entry and spread of WNV in North America.
- To examine WNV's impact on wild bird populations, genetic changes, and transmission.
Main Methods:
- Literature review of WNV emergence and spread in North America.
- Analysis of WNV impact on avian and equine populations.
- Review of WNV genetic evolution and transmission dynamics.
Main Results:
- WNV has spread across the USA, Canada, Caribbean, Mexico, Central America, and South America.
- Over 300 bird species have been affected, with significant population declines in some.
- Thousands of horses and over 30,000 Americans have experienced clinical illness, with over 1,000 deaths.
Conclusions:
- WNV has become a significant public health and ecological concern in North America.
- Understanding WNV's epidemiology, host interactions, and evolution is crucial for control.
- Ongoing surveillance and research are necessary to manage WNV transmission.
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