Legendary Equine Disease Outbreaks
In 2010 Iceland's population of 77,000 horses faced exposure to a pathogen they'd never encountered. | Photo: iStock

A look back at seven eye-opening equine epidemics in the past 100 years

Outbreak. The word itself can be terrifying, sounding like some kind of prison escape involving dangerous inmates. And in a way, that’s exactly what it is—but on a much larger scale. Billions of pathogens escape their hosts and slip into farms, barns, stalls, tack, equipment, and, inevitably, horses. Worse, they reproduce, sending out more of their destructive kind, wreaking havoc at alarming rates and causing illness, death, and financial losses.

Getting outbreaks under control can be tricky, costly, and frustrating. Some happen because of biosecurity oversights; others occur due to a lack of understanding of how diseases function. Some even occur as a result of malicious intent.

The history of equine science is full of stories about devastating outbreaks. While their trails of destruction are tragic, their tales of management and resolution are heroic. Join us as we look back at some of the world’s most legendary equine outbreaks and what we’ve learned from them.

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