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Encephalitic alphaviruses.
Michele A Zacks1, Slobodan Paessler
1Galveston National Laboratory, Department of Pathology, University of Texas Medical Branch, G.170 Keiller Building, Galveston, TX 77555-0609, United States.
Veterinary Microbiology
|September 25, 2009
Summary
This review examines encephalitic alphaviruses like Western (WEEV), Eastern (EEEV), and Venezuelan equine encephalitis virus (VEEV). These neuroinvasive viruses cause mild to severe neurological symptoms in humans and equines across the Americas.
Area of Science:
- Virology
- Neuroscience
- Epidemiology
Background:
- Encephalitic alphaviruses, including Western (WEEV), Eastern (EEEV), and Venezuelan equine encephalitis virus (VEEV), are zoonotic pathogens within the Togaviridae family.
- These viruses are neuroinvasive, capable of causing neurological conditions in humans and equines, ranging from mild febrile illness to severe encephalitis.
- Geographical distribution varies, with WEEV and EEEV prevalent in North America and VEEV primarily in Central and South America.
Purpose of the Study:
- To review zoonotic, encephalitic alphaviruses.
- To discuss their geographical distribution, vectors, and zoonotic potential.
Main Methods:
- Literature review of encephalitic alphaviruses.
- Analysis of geographical distribution data.
- Examination of vector species and zoonotic potential.
Main Results:
- WEEV distribution spans the U.S. and Canada.
- EEEV is found along the U.S. Gulf and Atlantic coasts, and in the Midwest and Canada.
- VEEV transmission is concentrated in Central and South America.
Conclusions:
- Encephalitic alphaviruses pose significant public health risks in the Americas.
- Understanding their distribution, vectors, and zoonotic potential is crucial for disease control.
- Further research into these viruses is warranted.
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