John Snow is best known for his work on identifying the origin of a Cholera outbreak. By logging cases by their address, he was able to identify a common factor in the fatalities of some 500 people. The study, centred around the junction of Cambridge and Broad Streets in Golden Square, London, made a link to the water pump at the junction of those two streets. His findings were corroborated by visual inspections of water quality at the site and the consequent removal of the water pump. Removing the pump had an immediate positive impact. John Snow had made the link between Cholera and the water supply. This, coupled with the breakthrough of identifying the Cholera disease as a distinct scientific entity led to improvements in Public Health and a reduction in the number of deaths caused by Cholera and other waterborn diseases.
John Snow and the Broad Street Pump
For a detailed audio visual account of John Snow’s work and his significance, visit this site. Here you will find a lengthy account of Snow’s work, methods and importance with audio narration provided by one of the leading historians of this period.
Source 1
The most terrible outbreak of cholera which ever occurred in this kingdom, is probably that which took place in Broad Street, Golden Square, and the adjoining streets, a few weeks ago. Within two hundred and fifty yards of the spot where Cambridge Street joins Broad Street, there were upwards of five hundred fatal attacks of cholera in ten days. The mortality in this limited area probably equals any that was ever caused in this country, even by the plague; and it was much more sudden, as the greater number of cases terminated in a few hours. The mortality would undoubtedly have been much greater had it not been for the flight of the population. Persons in furnished lodgings left first, then other lodgers went away, leaving their furniture to be sent for when they could meet with a place to put it in. Many houses were closed altogether, owing to the death of the proprietors; and, in a great number of instances, the tradesmen who remained had sent away their families: so that in less than six days from the commencement of the outbreak, the most afflicted streets were deserted by more than three-quarters of their inhabitants.
There were a few cases of cholera in the neighborhood of Broad Street, Golden Square, in the latter part of August; and the so-called outbreak, which commenced in the night between the 31st August and the 1st September, was, as in all similar instances, only a violent increase of the malady. As soon as I became acquainted with the situation and extent of this irruption of cholera, I suspected some contamination of the water of the much-frequented street-pump in Broad Street, near the end of Cambridge Street; but on examining the water, on the evening of the 3rd September, I found so little impurity in it of an organic nature, that I hesitated to come to a conclusion. Further inquiry, however, showed me that there was no other circumstance or agent common to the circumscribed locality in which this sudden increase of cholera occurred, and not extending beyond it, except the water of the above mentioned pump. I found, moreover, that the water varied, during the next two days, in the amount of organic impurity, visible to the naked eye, on close inspection, in the form of small white, flocculent particles; and I concluded that, at the commencement o the outbreak, it might possibly have been still more impure. I requested permission, therefore, to take a list, at the General Register Office, of the deaths from cholera, registered during the week ending 2nd September, in the subdistricts of Golden Square, Berwick Street, and St. Ann’s, Soho, which was kindly granted. Eighty-nine deaths from cholera were registered, during the week, in the three subdistricts. Of these, only six occurred in the four first days of the week; four occurred on Thursday, the 31st August; and the remaining seventy-nine on Friday and Saturday. I considered, therefore, that the outbreak commenced on the Thursday; and I made inquiry, in detail, respecting the eighty-three deaths registered as having taken place during the last three days of the week.
On proceeding to the spot, I found that nearly all the deaths had taken place within a short distance of the pump. There were only ten deaths in houses situated decidedly nearer to another street pump. In five of these cases the families of the deceased persons informed me that they always sent to the pump in Broad Street, as they preferred the water to that of the pump which was nearer. In three other cases, the deceased were children who went to school near the pump in Broad Street. Two of them were known to drink the water; and the parents of the third think it probable that it did so. The other two deaths, beyond the district which this pump supplies, represent only the amount of mortality from cholera that was occurring before the irruption took place.
With regard to the deaths occurring in the locality belonging to the pump, there were sixty-one instances in which I was informed that the deceased persons used to drink the pump-water from Broad Street, either constantly ,or occasionally. In six instances I could get no information, owing to the death or departure of every one connected with the deceased individuals; and in six cases I was informed that the deceased persons did not drink the pump-water before their illness.
On the Mode of Communication of Cholera, John Snow. 1855.
Links
http://www.bbc.co.uk/history/historic_figures/snow_john.shtml – excellent overview of John Snow’s work, provided by the BBC.
Public Health in the Industrial Revolution
Impact of new machines – Workhouses in Bradford and Leeds – Typhoid outbreaks 1830 – 1836 – Cholera, 1831 Outbreak – Poor Law Commission [1834, Report 1837] – Poor Law Commission 1835 – Bradford Woolcombers Report, 1837 – Report on the conditions of workers in Leeds, 1842 – Report on the sanitary Condition of the Labouring Classes, Chadwick 1842 – Health of Towns Association, 1844 – Health in Bradford in the mid 1840’s – Health in Manchester, 1844 – Public Health Act, 1848 – Working Conditions in Bradford, 1850 – Census figures: UK Population statistics 1831 – 1851 – John Snow’s work on Cholera, 1854 – Nightingale School of Nursing – Bradford Sewage Works, 1862 – Louis Pasteur: Germ Theory, 1865 – Second Reform Act [External] – Royal Sanitary Commission, 1869 – The Public Health Act, 1872 [External] – Public Health Act, 1875 [External] – Artizans and Labourers’ Dwellings Improvement Act, 1875 [External] – Tuberculosis Germ identified by Robert Koch, 1882 – Cholera Germ identified, 1883 – Health in Bradford, Margaret McMillan’s Report, 1890 – Report into the health of Children in Bradford, 1907 – Timeline of Public Health over time – Medicine and Treatments c1350-2018 – Themes in Medical History
Medicine Through time
Resources for Medicine Through Time – Prehistoric Medicine – Ancient Egyptian Medicine – Ancient Greek Medicine – Medicine in the Roman Empire – Medieval Medicine – Renaissance Medicine – Public Health in the Industrial Revolution – Fight against infectious disease – Modern Medicine