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In 1854 London doctor John Snow mapped the deaths in a cholera outbreak in Soho and saw that they clustered around a single public water pump on Broad Street. He persuaded the parish to remove the pump's handle, and gave strong evidence that cholera spreads through dirty water.

Soho, London, 1854

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The story behind the card

More than 600 people died in the outbreak, over 300 of them in its first ten days. Most doctors then blamed 'miasma', bad air from rotting matter. Snow, also a pioneer of anaesthesia, drew a map with a bar for each death and talked to families, helped by the local curate Henry Whitehead. He noticed that workers at the nearby brewery, who were given beer instead of water, escaped the disease. The pump handle came off on 8 September, but the outbreak was already fading. Whitehead later found the likely source: a cesspit about a metre from the well, into which water from a sick baby's nappies had drained. Officials refitted the handle and rejected Snow's idea; he died in 1858, before it was accepted.

Türkçe oku
Londralı hekim John Snow, 1854'te Soho'daki bir kolera salgınında ölenleri haritaya işledi ve ölümlerin Broad Street'teki tek bir su pompasının çevresinde toplandığını gördü. Yetkilileri pompanın kolunu söktürmeye ikna etti ve koleranın kirli suyla bulaştığına dair güçlü bir kanıt ortaya koydu.
Soho, Londra, 1854

Salgında 600'den fazla kişi öldü; bunların 300'ü aşkını ilk on günde hayatını kaybetti. Hekimlerin çoğu o dönem hastalığı çürüyen maddelerden yayılan kötü havaya, yani “miasma”ya bağlıyordu. Anestezinin öncülerinden de olan Snow, her ölüm için bir çizgi çektiği bir harita hazırladı ve mahallenin papazı Henry Whitehead'in yardımıyla ailelerle konuştu. Yakındaki bira fabrikasında su yerine bira içen işçilerin hastalanmadığını fark etti. Pompanın kolu 8 Eylül'de söküldü, ama salgın zaten geriliyordu. Whitehead daha sonra büyük olasılıkla kaynağı da buldu: Kuyunun bir metre kadar yakınındaki bir fosseptik çukuruna, hasta bir bebeğin bezlerinin yıkandığı su akmıştı. Yetkililer kolu yeniden taktı ve Snow'un görüşünü reddetti. Snow 1858'de, fikri kabul görmeden öldü.

Sources and further reading

Background reading: John Snow
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