

History of Medicine
John Snow, a hero of Public Health and Epidemiology, and his time
There is more to know about his story – it is not just only about cholera and the water pump
of the Golden Square District in London. Without knowing the ultimate cause of the
disease, Snow could convincingly demonstrate that polluted water was instrumental in the
transmission of the deadly epidemic. His investigations into the spread of cholera within
London in the middle of the 19
th
century made him the ‘father of epidemiology’. He did not
succeed in bringing down the miasma theory, but his methods of investigation are still
exemplary ways of detecting the mode of transmission and source of outbreaks of epidemics
of infectious diseases.
Teaching public health to medical students can be frustrating. I don’t say this about
Thailand. I am referring to medical students in my country of
origin. Their interest in public health, or social medicine as it was
called, was less than enthusiastic. Sometime I could not resist
exposing them to a rush of adrenalin when it came to examining
them in the final ‘State Examination’. One of my introductory
questions was, ‘What could be taken as the symbol of public health
and especially epidemiology?’ In introducing my question I did
remind the candidate about the symbol of medicine being the Staff
of Aesculapius. In my introductory lecture about epidemiology I
mentioned that the drawing of some street pump might, like the
Staff of Aesculapius, be taken as the symbol of epidemiology, if
not of public health, because it refers to the story of the cholera in
London in the middle of the 19
th
century and the investigation of
Snow into the cause of the epidemic. This event could be
considered as a milestone in epidemiological investigations and the fight against a disease
which was exposing millions at risk to a cruel death. Since it was not compulsory for the
students to attend the lecture but only to attend a seminar where basic issues were no longer
discussed, none of the candidates could answer correctly. Finally, I
had to abandon the question, because the candidates distributed
protocols about the examination questions for the use of the next
batch of students being examined. I must add that of course I didn’t
let the student fail for not knowing an answer to this question.
My guess is that the story of the street water pump in
London’s Golden Square District of Soho is on the agenda of every
introductory lecture in epidemiology and public health all over the
world. What students usually remember is that John Snow
dismantled the handle of that pump because the water was
Replica of Broad Street
Pump -Photo: F.P. Schelp