During the mid-1800s, there were two major theories on the cause of cholera being debated widely in medical circles throughout London. The organism that caused cholera, Vibrio cholerae, was not yet known and would not be until 1883, twenty-five years after the death of John Snow. In that year, Robert Koch, a German physician and bacteriologist, […]

One of my favorite data visualizations of all time is John Snow’s “Ghost Map” that helped identify the cause of the 1854 London cholera epidemic. I am currently reading Steven Johnson’s exciting book on this tragic chapter in London’s history. The book is titled The Ghost Map: The Story of London’s Most Terrifying Epidemic – […]