In the late 19th century, American cities moved to a soundtrack of clopping and clanking. Horses pulled commuters on streetcars, hauled construction materials for new buildings, carted groceries to homes, and conveyed patrons to theaters and baseball games.
But in late September 1872, horses fell sick on several farms near Toronto. Within days, a veterinarian found an additional 14 sick horses in the city. Within a week, the count grew to 600. The mysterious “Canadian horse disease” spread quickly, following rail lines into bustling cities and knocking out the workhorses that had powered the United States into a new era.
A fire devastated Boston’s commercial district, in part because horses were too sick to haul pump wagons. In New York, boxes lay untouched at railroad depots and city piers, among the busiest in the world. People lost work. Garbage went uncollected, mail undelivered. Political rallies, just weeks ahead of the presidential election, were canceled. Streets fell silent in such far-flung cities as Baltimore, Chicago, New Orleans and San Francisco. In D.C., streetcar service was shut down, as was horse- and mule-drawn traffic on the C&O Canal.
Known as the Great Epizootic, the outbreak of what was later determined to be the equine flu hit the vast majority of the country’s horses between October 1872 and March 1873, temporarily paralyzing cities in a crisis “comparable to what would happen today if gas pumps ran dry or the electric grid went down,” University of Tennessee historian Ernest Freeberg wrote.
Fortunately, the crisis was short-lived. Most horses rallied, and life in each locale resumed within several weeks. But the 150-year-old episode serves as an early example of how vulnerable modern life can be to a disease outbreak among animals. It’s a strikingly familiar theme at a time when an outbreak of avian flu has helped send egg prices soaring (and has infected some mammals) — and when a virus believed to have started in animals in a Chinese open-air market jumped into humans and shut down much of the globe starting in 2020.
Though the 19th century was marked by the advent of steam power, only horses were nimble enough to move within fast-expanding cities. Horses were the “invisible labor force” behind everything from international shipping to local entertainment, Oliver Lazarus, a Harvard doctoral candidate in the history of science, wrote for the Gotham Center for New York City History.