Café Scientifique: 11 November 2013 ‘John Snow Bicentenary,
Cholera Epidemiology,
the Isle of Wight and Haiti’.
My talk - not just a narrative account of medical history!
Modest aim of presentation : to give insight into how science advances & to provoke discussion
Greatest Doctor of all time?
Type question into
Greatest Doctor of all time?
Greatest Doctor of all time?
Hospital Doctor Asked its readership in March 2003
Greatest Doctor ever?
Greatest Doctor ever:
1. John Snow (1813-1858)
2. Hippocrates (460-370 BC)
3. Dame Cicely Saunders (1918-2005)
John Snow – London’s number 1 Anaesthetist
End 1846 ‘Ether’ arrives from Boston
1847 Book ‘On the Inhalation of the Vapour of Ether in Surgical Operations’
Anaesthetist to royalty 1853 Provided anaesthetic for the birth of Prince Leopold (no. 8) ‘Dr Snow gave that blessed chloroform and the effect was soothing, quieting, and delightful beyond measure’ 1857 Birth of Princess Beatrice (no. 9) (1858 Posthumous book ‘On Chloroform and Other Anaesthetics’ Snow is said to have given 11,000 anaesthetics without a death)
Anaesthetics – not enough to account for increasing veneration of Snow during last century
Reputation:
Anaesthetics – not enough to account for increasing veneration of Snow during last century
Reputation:
Cholera - But why did Snow bother?
John Snow Pub
But he was teetotal
London School of Hygiene & Tropical Medicine
John Snow Lecture Theatre
College of the University of Durham Founded 2001
Waves of cholera/deaths E & W IOW (Snow)
1832 22k 2 Apprentice in Sunderland
1848/9 53k 188 Used IOW data
1854 20k 35 Broad Street
South London water supply
1866 14k 125 Dead
Snow • Had a strong conviction
that cholera was transmissible by water, food and person-to-person
• Applied the science then available
• But his findings not endorsed by the medical or political establishment
Transmission via water
1850: JS founding member of the Epidemiological Society of London
Snow called in Hassall
Hassall’s 1854 illustration of rice-water evacuations
Great missed opportunity
Filippo Pacini
Pacini now acknowledged as discoverer of cholera organism Work of Louis Pasteur and Robert Koch was to follow
Broad Street Pump
Rev Henry Whitehead
Context provided by modern historians
Paper 1990:
‘Who made
John Snow
a hero’
Charles Creighton
1894 ‘History of epidemics in Great Britain’
Two volumes
16 000 pages
One sentence on Snow
Major Greenwood
1934 ‘Epidemics
and Crowd Diseases’
Chapter on Cholera
But no mention of Snow
Historians point out:
• in the 1840s and 50s there was much confusion over cholera
• Many ‘pet theories’ were published
• Snow’s work did not lead to a scientific revolution
Snow was made famous by Hampton Frost
• 1936 republished second edition of ‘Snow on Cholera’
• Used Snow’s outbreak maps
as a John Hopkins class exercise
• Hampton’s pupils wrote the textbooks of the second half
of the 20th century
Good story:
• Poor boy made good
• Solitary medical genius
• Public Health hero
Good scientist?
Tom Koch: John Snow –
• Rushed to print
• Misused data
(Snow did not endear himself
to Thomas Wakley)
But he was right!
First 1848/49 IOW death from cholera 20th Dec 1848: The surgeon of the Cowes
District reported to the Guardians of the Poor that a case of malignant Cholera he had under his care had terminated fatally. The name of the Individual was Charles Nutkins, a sailor, 27 years of age who returned on the evening of the 15th December from Rotterdam via London and Southampton and died in the night of the 16th.
National enquiry conducted in 1849 of previous year’s outbreak by Provincial Medical and Surgical Association
Published a questionnaire in its Journal
Few responded but
Mr Bloxam of
Newport did
Read by Snow who contacted Mr Bloxam for more detail
Snow published the Carisbrooke cluster in the second edition of his ‘On the Mode’ as an example of the transmission of Cholera via food
12 January 2010: Haitian Earthquake
Moment magnitude scale 7.0 Depth 8 to 10 Km 15 Km southwest of Port-au-Prince 220,000 killed
Haitian Earthquake
2010 Haitian outbreak of Cholera No evidence of cholera in Haiti before 2010
Since Oct 2010, has killed 8,361 (17 Oct 2013)
Haitian outbreak of Cholera: Sudden, and initially localised
Artibonite District
UN: ‘the main task is to control the outbreak not look for the source’
Jan 2011 New England Journal of Medicine
‘Haitian outbreak
strain shares
ancestry with
recent South Asian
strains and not
those circulating
in Latin America
and East Africa’
UN independent panel report
‘The sanitation conditions at the (Nepalese) camp were not sufficient to prevent faecal contamination’
UN independent panel report
The outbreak could not have occurred ‘without simultaneous water, sanitation and health care system deficiencies’
‘Outbreak caused by the confluence of circumstances - not the fault of or deliberate action of a group or individual’
(Oct 2013: Haitian strain found in Mexico)
Tom Koch
‘Science is not about being right but convincing others you are right’
Tom Koch
‘When in the thick of another epidemic, raise a
glass of lemonade to John Snow,
but follow it with
a chaser for all the
other alcoholics
who laboured in
the field’
Questions/Conclusion • John Snow is venerated by the specialty of public
health – but should he be? Should science have heroes?
• As a scientist, is it enough just to be right? • The Isle of Wight’s connection with cholera and
Snow’s bicentenary (Carisbrooke cluster/Hassall at Ventnor/Queen Victoria) have been commemorated - just in time.
• Organism genetics (bacteria ‘fingerprinting’) is revolutionising outbreak investigation.
"You and I", he (Snow) would say to me, "may not live to see the day, and my name may be forgotten when it comes, but the time will arrive when great outbreaks of cholera will be things of the past; and it is the knowledge of the way in which the disease is propagated which will cause them to disappear.“ Rev Henry Whitehead at his farewell dinner