John Snow, M.D. (1813-1858), a legendary figure in epidemiology, provided
one of the earliest examples of using epidemiologic methods to identify risk
for disease and recommend preventive action.1 Best
known for his work in anesthesiology, Snow also had an interest in cholera
and supported the unpopular theory that cholera was transmitted by water rather
than through miasma (i.e., bad air).
On August 31, 1854, London experienced a recurrent epidemic of cholera;
Snow suspected water from the Broad Street pump as the source of disease.
To test his theory, Snow reviewed death records of area residents who died
from cholera and interviewed household members, documenting that most deceased
persons had lived near and had drunk water from the pump. Snow presented his
findings to community leaders, and the pump handle was removed on September
8, 1854. Removal of the handle prevented additional cholera deaths, supporting
Snow’s theory that cholera was a waterborne, contagious disease. Despite
the success of this investigation, the cause of cholera remained a matter
of debate until Vibrio cholerae was isolated in 1883.
Snow’s studies and the removal of the pump handle became a model
for modern epidemiology. To recognize his pioneering work, this issue of MMWR highlights public health actions guided by epidemiologic
data to control a modern epidemic of cholera, detect and prevent adverse reactions
to vaccinations, stop an epidemic of aflatoxin poisoning, and correct environmental
causes of waterborne outbreaks.
150th Anniversary of John Snow and the Pump Handle. JAMA. 2004;292(16):1950. doi:10.1001/jama.292.16.1950