Why Did Western Equine Encephalitis Vanish? Harvard Scientists Unveil a Viral Mystery

The fate of a mutating virus provides crucial insights for preparing for pandemics.
Over the past century, a previously lethal mosquito-borne virus has undergone evolutionary changes that have rendered it harmless to humans. Recent research has demonstrated that these alterations in the virus’s targeting of human cells correlate with a decrease in related illnesses and fatalities. These insights provide valuable lessons in virology, potentially enhancing preparedness for future viral outbreaks.

The story of the rise and fall of western equine encephalitis as a lethal disease offers essential lessons about how a pathogen can gain or lose its ability to jump from animals to humans.