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John Snow's Cholera Map - Tutorial

Recreating the map that birthed epidemiology

## Visualizing an outbreak Due to rapid growth and poor sanitization, London suffered many devastating cholera outbreaks in the mid 1800's. Up into the 1854 Broad Street outbreak in Soho, the prevailing "miasma" theory was that pollution or a noxious form of "bad air" causes the spread of diseases like cholera or the Black Death. John Snow, a renown British physician, a skeptic to this theory hypothesized that Cholera was passed by an agent in contaminated water. John Snow was able to prove this theory through his now-famous map that plotted the locations of deaths which helped identify the source of the outbreak a public water pump on broad street. John Snow's ground breaking working to collect and visualize data in an attempt to explain the cause of disease is one of the reason's he is recognized as one of the founder's of modern epidemiology. # Recreating John Snow's Cholera Map Below is a video tutorial to create the map above. ### Data Download (links below) the location of the water pumps and deaths in geojson format. Special thanks to [Dr. Robin Wilson](https://blog.rtwilson.com/john-snows-cholera-data-in-more-formats/) who originally digitized this data! * [Water Pumps](https://raw.githubusercontent.com/onaio/akuko-data/main/john-snow-choleramap/cholera-pumps.geojson) * [Cholera Deaths](https://raw.githubusercontent.com/onaio/akuko-data/main/john-snow-choleramap/cholera-deaths.geojson) Upload each file to create a source representing the cholera deaths and water pumps #### Style URL To customize the basemap, click on Style and select Custom Style URL. Paste in the following style url: `mapbox://styles/ona/cl4kpj4gc001w15qu60eszsy4` ### Create your own [Signup](https://app.akuko.io/user/sign-up) for a free beta account and create your first map today!