A child gets vaccinated during an oral cholera vaccine campaign amid an acute cholera outbreak in Sanaa, Yemen, in 2019. File Photo by Yahya Arhab/EPA

Many Americans have heard about cholera only from The Oregon Trail, the retro computer game in which players try to get their 1830s pioneers to the Oregon Territory. If your wagon train comes down with this highly contagious bacterial infection, the pioneers could die from diarrhea and dehydration before they get out of Nebraska.

In the 21st century, the U.S. records fewer than 20 cholera cases per year, nearly all of them in travelers who were infected abroad.

While cholera has nearly disappeared from wealthy countries, it remains one of the world's deadliest waterborne diseases in places where clean water and basic healthcare are unreliable.

The latest reminder came in the summer of 2026 in Sudan, where a long conflict has devastated hospitals and water systems, allowing cholera to spread rapidly.