John Snow’s Investigation on Cholera Outbreak

Subject: Epidemiology
Pages: 2
Words: 572
Reading time:
3 min

Soho, London, in August 1854, was struck with a chronic outbreak of an infectious disease known as cholera. It is a gastrointestinal disease triggered by a bacterium, Vibrio cholerae. It can also prevail in areas with poor sanitation and poor hygiene of water and food. Its symptoms include nausea, vomiting, and watery diarrhea, which can cause death due to severe dehydration if not stabilized. It was in Soho where Dr. John Snow was a surgeon and general medical practitioner during the time of the outbreak. He likely prevented more people’s death since the disease had already claimed many of their lives.

The outbreak made Snow doubtful of the then-existing theory behind the disease. He based his belief on sewage dumped into the rivers and cesspools near town wells to cause cholera outbreaks as it contaminates the water supply. In an attempt to prove his model, he commenced his investigation immediately after the outbreak. He started by conversing with the residents and quickly realized that Broad Street’s public water pump was the epidemic source. He used the local hospital’s information he was working at and extracted more information from public records. He also specifically questioned the people if they had consumed water from the pump. He utilized this information to create a dot map illustrating the cluster of the disease cases around the pump. After a month of research, he forwarded his results to the local authority and convinced them to take off the pump to prevent residents from fetching from it (Walford, 2020). After a short while, the heartbreak ended.

Measles is a very contagious disease to the point that about 90% of persons around the sick person would probably contract it if one person has it. As a health official, I would be interested in understanding the symptoms and the mode of transmission of the disease. I would conduct interviews on the affected group and the public at large to obtain more information about the probability of the prevalence of measles within the community. For example, the onset of the first suspected measles case in Disneyland was of a child, 11 years of age, who was not vaccinated. This happened after a notable history of travel to one of the parks in California. On the same day of the visit, it was suspected that the measles cases had increased to four, which eventually added up gradually. If immediate isolation of the first case had been done, the number of cases would not have significantly risen. The virus is known to survive two hours in an airspace where an infected person coughed or sneezed. Based on the fact that one can get the disease simply by being in the same room with an infected person even if he has already left, I would make my conclusions and recommendations. The recommendations would go a long way to curb the continuous ignorant spreading of the disease among the population.

In conclusion, as a health official, I would recommend that vast immunization against the disease be practiced on the people. Also, the first case of the illness should be isolated to prevent any further spread of the disease. Another preventive measure to take is to eradicate the prevalence from all the world regions through vaccination. This will help prevent the cases that could emerge out of interacting with people from different countries who might not know that they already have the disease despite administering vaccines.


Walford, N. S. (2020). Demographic and social context of deaths during the 1854 cholera outbreak in Soho, London: A reappraisal of Dr John Snow’s investigation. Health & Place, 65, 102402.