1854 Broad Street cholera outbreak
The Broad Street cholera outbreak (or Golden Square outbreak) was a severe outbreak of cholera that occurred in 1854 near Broad Street (now Broadwick Street) in Soho, London, England, and occurred during the 1846–1860 cholera pandemic happening worldwide. This outbreak, which killed 616 people, is best known for the physician John Snow's study of its causes and his hypothesis that germ-contaminated water was the source of cholera, rather than particles in the air (referred to as "miasma").[1][2] This discovery came to influence public health and the construction of improved sanitation facilities beginning in the mid-19th century. Later, the term "focus of infection" started to be used to describe sites, such as the Broad Street pump, in which conditions are favourable for transmission of an infection. Snow's endeavour to find the cause of the transmission of cholera caused him to unknowingly create a double-blind experiment.
Date
Snow's post-outbreak evaluation[edit]
Snow's analysis of cholera and cholera outbreaks extended past the closure of the Broad Street pump. He concluded that cholera was transmitted through and affected the alimentary canal within the human body. Cholera did not affect either the circulatory or the nervous system and there was no "poison in the blood...in the consecutive fever...the blood became poisoned from urea getting into the circulation".[22] According to Snow, this "urea" entered the blood through kidney failure. (Acute kidney failure is a complication of cholera.)[23]
Therefore, the fever was caused by kidney failure, not by a poison already present in the subject's bloodstream. Popular medical practices, such as bloodletting, could not be effective in such a case. Snow also argued that cholera was not a product of Miasma. "There was nothing in the air to account for the spread of cholera".[22] According to Snow, cholera was spread by persons ingesting a substance, not through atmospheric transmittal. Snow cited a case of two sailors, one with cholera and one without. Eventually the second became sick as well from accidentally ingesting bodily fluids of the first.
Board of Health[edit]
The Board of Health in London had several committees, of which the Committee for Scientific Inquiries was placed in charge of investigating the cholera outbreak. They were to study the atmospheric environment in London; however, they were also to examine samples of water from several water companies in London. The committee found that the most contaminated water supply came from the South London water companies, Southwark and Vauxhall.[2]
As part of the Committee for Scientific Inquiries, Richard Dundas Thomson and Arthur Hill Hassall examined what Thomson referred to as "vibriones". Thomson examined the occurrence of vibriones in air samples from various cholera wards and Hassall observed vibriones in water samples. Neither identified vibriones as the cause of cholera.[2]
As part of their investigation of the cholera epidemic, the Board of Health sent physicians to examine in detail the conditions of the Golden Square neighbourhood and its inhabitants. The Board of Health ultimately attributed the 1854 epidemic to miasma.[2]
Dr Edwin Lankester's evaluation[edit]
Dr Edwin Lankester was a physician on the local research conglomerate that studied the 1854 Broad Street Cholera Epidemic. In 1866, Lankester wrote about Snow's conclusion that the pump itself was the cause of the cholera outbreak. He agreed with Snow at the time; however, his opinion, like Snow's, was not publicly supported. Lankester subsequently closed the pump due to Snow's theory and data on the pattern of infection, and infection rates dropped significantly. Lankester eventually was named the first medical officer of health for St James's parish in London, the same area where the pump was located.[22]
Broadwick Street pump in the 21st century[edit]
A replica pump was installed in 1992 at the site of the 1854 pump. Every year the John Snow Society holds "Pumphandle Lectures" on subjects of public health. Until August 2015, when the pump was removed due to redevelopment, they also held a ceremony here in which they removed and reattached the pump handle to pay tribute to Snow's historic discovery. The original location of the historic pump is marked by a red granite paver. In addition, plaques on the John Snow pub at the corner describe the significance of Snow's findings at this site.[26]
The new location of the pump whose handle John Snow removed.
A wider image of the pump, with the red granite slab in view in the bottom-left corner.
The plaque that rests on the new foundation of the pump.
A plaque marking the significance of the red granite and the pump. Located on the wall of the John Snow pub, straight across from the pump itself.
Broadwick Street showing the John Snow memorial and public house. The memorial pump was removed due to new construction in March 2016. It was replaced, on the pavement outside the pub, in 2019. A plaque affixed to the public house reads: The Red Granite kerbstone mark is the site of the historic Broad Street pump associated with Dr John Snow's discovery in 1854 that cholera is conveyed by water.
