The Germ Theory of Disease
Herman Gordon, Ph.D. Univ. of Arizona
What was it like before GToD?
Spontaneous generation / The Wrath of God The Miasma Theory of Disease The concept of contagiousness without the concept of contagion
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An Exercise in Problem Solving What was it like before the GToD?
1546 Girolamo Fracastoro
1673 Antonie Philips van Leeuwenhoek
proposed that epidemic disease was spread by “spores”
observed microbes in a microscope
http://en.wikipedia.org/wiki/Image:Antoni_van_Leeuwenhoek.png
http://en.wikipedia.org/wiki/Image:Antoni_van_Leeuwenhoek.png
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1835 Agostino Bassi
1843 Oliver Wendell Holmes
argued that disease could be transferred between patients by doctors and nurses who didn’t wash their hands
stated the Germ Theory of Disease for the 1st time
http://en.wikipedia.org/wiki/Image:Antoni_van_Leeuwenhoek.png
http://en.wikipedia.org/wiki/Image:Oliver_Wendell_Holmes.jpg
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Described a “living entity” in the form of a contagious and visible white dust as the cause of the silk epidemic in Europe. Later isolated as a fungus and named after him. Recommended disinfection and destruction of infected silk larvae. 1845 postulated that living agents could also transmit human disease.
Remarkable because there was little concept of germs at this time!
1847 Ignaz Semmelweiss
independently discovered the need for hand-washing between patients, but failed to convince others
1849-1854 John Snow
the father of epidemiology, figured out that bad well water caused cholera –!not bad air
http://en.wikipedia.org/wiki/Image:Ignaz_Semmelweis.jpg
http://en.wikipedia.org/wiki/Image:John_Snow.jpg
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Cholera in London
1854 Filippo Pacini
isolated cholera bacillus
http://en.wikipedia.org/wiki/Image:John_Snow.jpg
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http://en.wikipedia.org/wiki/Image:Snow-cholera-map-1.jpg
Also discovered the Pacinian corpuscle deep touch sensor. Discovery of cholera bacillus was rejected because the Miasma Theory of Disease was dominant in Italy at the time. Rediscovered by Koch 30 years later.
1860-65 Louis Pasteur(ization)
showed that microbes caused fermentation effectively advocated the GToD, and hence became its “father”
Proof of Biogenesis
http://history.amedd.army.mil/booksdocs/misc/evprev/fig21.jpg
http://en.wikipedia.org/wiki/Image:Coldecygne.svg
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Dramatic demonstration similar to Feynman’s freezing of the rubber gasket in a glass of ice water during the Challenger enquiry.
1867 Joseph Lister(ene)
1914 Joseph Goldberger
Pushed anti-septics
figured out that pellagra was NOT caused by infectious agents
http://en.wikipedia.org/wiki/Image:Joseph_Lister.jpg
from the CDC Public Health Image Library (PHIL #8164)
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Lessons from History
History repeats itself Truth can be rejected for stupid reasons
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