John Snow

Medicine British 1813 – 1858 355 quotes

A founder of modern epidemiology, he traced the source of a cholera outbreak in London to a contaminated water pump.

Most quoted

"The facts are so numerous and so striking, that they appear to me to amount to a demonstration, that the water of the Broad Street pump was the cause of the late outbreak of cholera in St. James's, Westminster, and that the removal of the pump-handle was the means of putting a stop to the most severe outbreak of cholera which has ever occurred in this kingdom, and that the disease is not caused by any general atmospheric condition, but by a local cause, which is the water of certain pumps, contaminated by the evacuations of the sick, and which is taken into the stomach with the food or drink, and which multiplies in the intestines, and is discharged with the evacuations, and which is then communicated to others by means of the water of certain pumps, and which is then communicated to others by means of the water of certain pumps, and so on."

— from On the Mode of Communication of Cholera (2nd ed.), 1855

"The evidence is as complete as the nature of the case admits of, that the water of the Broad Street pump was the cause of the cholera, and that the removal of the pump-handle was the means of putting a stop to the most severe outbreak of cholera which has ever occurred in this kingdom, and that the disease is not caused by any general atmospheric condition, but by a local cause, which is the water of certain pumps, contaminated by the evacuations of the sick, and which is taken into the stomach with the food or drink, and which multiplies in the intestines, and is discharged with the evacuations, and which is then communicated to others by means of the water of certain pumps, and which is then communicated to others by means of the water of certain pumps, and so on, and so on."

— from On the Mode of Communication of Cholera (2nd ed.), 1855

"The evidence is as complete as the nature of the case admits of, that the water of the Broad Street pump was the cause of the cholera, and that the removal of the pump-handle was the means of putting a stop to the most severe outbreak of cholera which has ever occurred in this kingdom, and that the disease is not caused by any general atmospheric condition, but by a local cause, which is the water of certain pumps, contaminated by the evacuations of the sick, and which is taken into the stomach with the food or drink, and which multiplies in the intestines, and is discharged with the evacuations, and which is then communicated to others by means of the water of certain pumps, and which is then communicated to others by means of the water of certain pumps, and so on."

— from On the Mode of Communication of Cholera (2nd ed.), 1855

All quotes by John Snow (355)

The most frequent and fatal of the diseases which affect the human race, is cholera.

On the Mode of Communication of Cholera 1849

It is not by the atmosphere that the disease is propagated, but by something which is swallowed.

On the Mode of Communication of Cholera 1849

The disease is communicated by the evacuations of the sick, and by these alone.

On the Mode of Communication of Cholera 1849

The cholera poison multiplies itself in the human body.

On the Mode of Communication of Cholera 1849

The disease is not contagious in the common sense of the word, but is communicated by the ingestion of matter containing the specific poison.

On the Mode of Communication of Cholera 1849

The great cause of the propagation of cholera is the contamination of the water used for drinking.

On the Mode of Communication of Cholera (2nd edition) 1855

The disease is not spread by effluvia, but by the actual contact of the morbid matter with the alimentary canal.

On the Mode of Communication of Cholera (2nd edition) 1855

The Broad Street pump is the most terrible example of the communication of cholera by water.

On the Mode of Communication of Cholera (2nd edition) 1855

If the water of the pump were removed, the epidemic would cease.

Letter to the St. James's Gazette 1854

The evidence, therefore, of the communication of cholera by water is of the most convincing kind.

On the Mode of Communication of Cholera (2nd edition) 1855

The disease is not communicated through the air, but through the alimentary canal.

On the Mode of Communication of Cholera (2nd edition) 1855

The removal of the pump-handle was followed by an immediate cessation of the epidemic.

On the Mode of Communication of Cholera (2nd edition) 1855

The disease is not due to any atmospheric influence, but to a specific poison.

On the Mode of Communication of Cholera (2nd edition) 1855

The evidence is so strong that it amounts to a demonstration.

On the Mode of Communication of Cholera (2nd edition) 1855

The disease is not a general affection of the system, but a local affection of the alimentary canal.

On the Mode of Communication of Cholera 1849

The poison of cholera is swallowed, and acts on the mucous membrane of the stomach and intestines.

On the Mode of Communication of Cholera 1849

The disease is not caused by any miasm or effluvium, but by a specific morbid matter.

On the Mode of Communication of Cholera 1849

The disease is not communicated by the breath, or by the skin, but by the evacuations.

On the Mode of Communication of Cholera 1849

The disease is not a fever, but a local affection of the alimentary canal.

On the Mode of Communication of Cholera 1849

The disease is not communicated by the air, but by the water.

On the Mode of Communication of Cholera (2nd edition) 1855