Western equine encephalitis virus: A comprehensive review of epidemics,transmission, hosts, and strategies for mitigation

Submitted by the MVCAC VVBD Committee

Wang L, et al. VIRULENCE. 2025, VOL. 16, NO. 1, https://doi.org/10.1080/21505594.2025.2580162 

ABSTRACT. Recent increases in cases of western equine encephalitis (WEE) in South America have raised significant concerns about the virus’s potential to cause an endemic disease due to its adaptation to mosquito vectors. Currently, there are no effective vaccines or treatments for WEEV, despite ongoing research into various biochemical products in animal models. The virus presents different pathological effects depending on the host. In humans, WEEV infection leads to central nervous system damage, resulting in encephalitis and severe neurological sequelae, which underscores theneed for further research into its pathogenic mechanisms. To enhance understanding of WEEV and address potential threats, this review focuses on the virus’s natural transmission cycle, the development of biochemical products for combating WEEV infection, and new diagnosis methods. It also highlights research on mechanisms in animal models, offering potential strategies for defending against WEEV.

Note: This paper did not review well the current risk assessment model and response in California which was created initially for WEEV and SLEV.