The 1854 London Cholera Outbreak

Cholera is an infection of the intestines caused by ingesting the bacterium Vibrio cholerae present in fecally contaminated water or food. Its presence is usually due to lack of access to safe water and proper sanitation. (1)

In its most severe form, there is a sudden onset of watery diarrhea that can lead to death by severe dehydration. It has a very short incubation period ranging from two hours to five days which can result in an explosive outbreak pattern. 

Dr. John Snow (1813 - 1858) was an English Physician who is considered to be the founder of modern epidemiology. He is best known for tracing the source of a deadly cholera outbreak to a contaminated water well on Broad Street in Soho, London in 1854. 

This tutorial will teach you how to re-create John Snow's famous cholera map using Google Fusion Tables. 

 

John Snow's Map of the Soho, London, Cholera Outbreak, first presented in December 1854. (click for larger view)

The EPIDEMIC

In 1854, London was a city with close to 2.5 million residents. Extreme poverty combined with a lack of sanitation infrastructure such as clean water and sewage systems made it the perfect environment for an outbreak of disease. As such, the city suffered many outbreaks over the course of its history. Leading up to the Summer of 1854, it had several large cholera outbreaks resulting in the deaths of tens of thousands of people. 

What makes the 1854 cholera outbreak in the Soho neighborhood of London's West End so important is that. You will learn about the major players involved while learning to use Fusion Tables to map the epidemic.  

 


LESSON 1: ORGANIZING & IMPORTING DATA into fusion tables

This lesson will teach you about the data format and how to load it into Fusion Tables.

  1. The data
  2. Required data formats
  3. Importing data into Fusion Tables
 Data tables

Data tables


 Heat map of the outbreak data

Heat map of the outbreak data

LESSON 2: VISUALIZING YOUR DATA IN fusion tables

This lesson will teach how to visualize your data once it has been loaded into Fusion Tables.

  1. Cards 
  2. Charts
  3. Maps

LESSON 3: PUTTING IT ALL TOGETHER

This lesson will teach you....

  1. The big picture 
  2. Ethical considerations
  3. Cholera today
 Scanning electron microscope (SEM) image of Vibrio cholerae

Scanning electron microscope (SEM) image of Vibrio cholerae


BEYOND THE MAPS

To learn more about Dr. John Snow, the London cholera investigation and his lasting impact on public health, visit the following:

  1. The John Snow Society - London, United Kingdom-based organization promoting the life and works of Dr. John Snow as well as providing a communication network for epidemiologists and others trained in his methodology around the world.
  2. On the Mode of Communication of Cholera - Dr. John Snow's original work hosted by the University of California at Los Angeles' Fielding School of Public Health. This is part of a larger site featuring an in-depth analysis by Dr. Ralph R. Frerichs of Dr. Snow's approach to tackling the outbreak highlighting other people, organizations and institutions involved. 
  3. London School of Hygiene and Tropical Medicine - Brief overview of Dr. Snow's life featuring a podcast dedicated to his work and legacy at the time of the 150th anniversary of his birth.
 Dr. John Snow, age 44, taken the year before his death in 1857.  Photograph, anonymous: Wellcome Historical Medical Museum & Library, London - Gordis L.  Epidemiology , WB Saunders, Philadelphia, 1996

Dr. John Snow, age 44, taken the year before his death in 1857.

Photograph, anonymous: Wellcome Historical Medical Museum & Library, London - Gordis L. Epidemiology, WB Saunders, Philadelphia, 1996


To learn more about cholera and ongoing outbreaks around the world, visit the following sites:

  1. World Health Organization (WHO) - Cholera page featuring up-to-date information on cholera outbreaks around the world as well as information on symptoms, diagnosis, treatment and vaccines.
  2. United States Centers for Disease Control and Prevention (CDC) - Cholera page with a global map highlighting countries with recent cholera outbreaks of as well as resources for outbreak response, training, and health promotion.

References

1. Updated Global Burden of Cholera in Endemic Countries - WHO 2017