First Cholera Pandemic
The first cholera pandemic spread from India to much of the world, killing millions
January 01, 1817
A Disease Born in Contaminated Water
Cholera is a bacterial infection caused by Vibrio cholerae, spread primarily through contaminated water and food. The disease causes severe watery diarrhea that can lead to fatal dehydration within hours if untreated. Cholera originated in the Ganges Delta of the Indian subcontinent. Between 1817 and the early 20th century, seven major cholera pandemics swept the globe, killing tens of millions of people on every inhabited continent. The second pandemic of the 1830s was particularly devastating, reaching North America and Europe for the first time.
John Snow and the Soho Outbreak
During London's 1854 cholera outbreak, physician John Snow conducted one of history's most famous public health investigations. He mapped the deaths and traced them to a single water pump on Broad Street in the Soho neighborhood. By persuading authorities to remove the pump handle, Snow helped stop the outbreak — and provided compelling evidence that cholera spread through water, not air. His work is considered the founding act of modern epidemiology, the science of tracking and controlling disease outbreaks.
Cholera in the Modern World
Cholera is preventable with clean water and sanitation systems. It largely disappeared from wealthy nations in the 20th century as cities built modern sewage and water treatment infrastructure. But it remains a serious threat in areas with inadequate sanitation. Major outbreaks have occurred in Haiti, Yemen, and parts of Africa in recent decades. A seventh pandemic has been ongoing since 1961. Oral rehydration therapy — replacing lost fluids with a simple water, salt, and sugar solution — has dramatically reduced cholera's death toll worldwide. Use our date calculator to track the pandemic timeline.