Cholera has been around for centuries — the ancient Greek physician Hippocrates seems to allude to it in his work — but for a long time it was restricted to the delta region of India's Ganges River. It wasn't until 1817 when, carried by travelers along trade routes, the disease spread throughout the rest of India and into what is now modern-day Burma and Sri Lanka. Referred to as "Asiatic cholera" by Britain and the U.S. (which would not be hit by the disease until the 1830s), it eventually reached the Philippines and even Iraq, where 18,000 people died during one three-week period in 1821. This was the first of seven cholera pandemics that have spread throughout the globe.