Source Identification of Cholera Outbreak

Year:　1854

Place:　London, UK

The Story:

In Europe in the 19th Century, people were suffering from occasional cholera outbreaks, which had been causing many deaths. One large outbreak occurred in London in 1854. In order to identify the source of the outbreak, Dr. John Snow prepared a map of a suspected location and put marks on places where people had gotten infected.
As he collected more and more data, he pinpointed a place where people were highly likely to be infected. Finally, he discovered that contaminated water in a well in the town was the source of the outbreak.

The Significance

This incident was resolved by Dr. Snow’s skillful analysis using infographics. This example shows that data visualization can help reveal new facts.