The Ghost Map

I read a book called The Ghost Map, which is about the discovery of the source of the cholera outbreak in London in 1854. It talks about the unique set of circumstances that gave John Snow a point a view that led him to the Broad street pump as the source of the outbreak. One thing that helped him was his experience with chloroform and ether, which had recently come into use in medicine. From experimentation on himself as well as his collection of lab animals, he was able to create a standard by which the gases were used. He was so renowned for his work in anesthetic gases, he was asked to administer chloroform to Queen Victoria during childbirth.

jonsnow lab

 

 

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Mortality and Morbidity in Human History: Cholera

Cholera probably originated in South Asia and made a home in the Ganges and the Yangtze Rivers. In Bengal, there’s actually a goddess of cholera. It didn’t make it into the west until 1817, most likely through armies first and then pilgrims filled in the gaps.

The first couple great pandemics were spread by British armies traveling between India, Persia and England and killed hundreds of thousands. Soldiers reportedly died as they marched, having only caught the disease that morning.

19thcenturynurses

19th century cholera ward

Cholera was brought to America in 1831. It went from Canada to New York State with the first documented case cited in June 26, 1832. American business being what is has always been, proved to be a vocal opposition to closing down public places because of the effect it would have on commerce. This tactic had been used to good effect elsewhere.

It was an Italian scientist, Filippo Pacini, that discovered the bug first sometime between 1854-63. Robert Koch rediscovered it in 1883 and got credit for it for decades. Not until the 1960’s was Pacini honored as the first to make the discovery when the bacteria that causes the disease was officially named Vibrio cholera Pacini.

Signs/symptoms

Cholera victims present with profuse diarrhea which has a characteristic “rice water” appearance. This quickly leads to dehydration. If not properly supported, the victim then experiences a drop in blood pressure as the body’s fluid levels decrease. This can cause collapse and renal failure as the kidneys fail to receive adequate perfusion.

Cholera is spread via contaminated water so it tends to not be a danger in developed nations. There are currently two cholera vaccines though neither are available in the U.S.. Sanitation and water treatment facilities are by far, the best way to prevent cholera outbreaks. In areas of the world where large numbers of people are living together without these things, outbreaks still occur. Last year, Yemen experienced an outbreak and currently, Kenya is experiencing one in the Daadab complex, which houses around 350,000 displaced people.

 

source: Plagues & Poxes: the Impact of Human History on epidemic disease

CDC

You know nothing Jon Snow

Actually, Ygritte said it more like, “YOU KNOW NUFFIN’ JON SNRRRR.”

But it’s not that Jon Snow anyway.

jonsnow

John Snow, the English Physician is kind of a rock star in epidemiology. He helped find the source of a cholera outbreak in London in 1854. By observation and interviews of affected people and those around them, he was able to trace the outbreak to a public water pump. The city soon shut it down by removing the handle and the epidemic subsided.