The Ghost Map, a book by Steven Johnson (Riverhead Books Publisher, NY. 2006), tells the story about a devastating outbreak of cholera in 1854 Victorian London. It is about the disease, the people, a map, and the investigation by two men who discovered the source of the spread of the disease.
Johnson is a masterful storyteller. He paints a vivid picture of London as a city of scavengers. I can see and smell the stench as Johnson describes the lives of many, especially the bone pickers (finders of carcasses), rag-gatherers, pure-finders (collectors of dog dung), sewer hunters, night-soil men, and others – the underclass of London who lived in a world of excrement and death. Johnson notes that the city had 2.5 million people in a space 30 miles in circumference, a crammed space with no public health department, no safe sewage removal, and no recycling. In 1851, London was the most populous city in the world. The scavengers played an important role in ‘recycling’ waste and discarded goods. Johnson goes on to describe the need for recycling to sustain life, how manure replenishes the earth so more crops could be grown. Human waste (night soil) was prized for use in fertilizing the soil for new crops. Houses and other living establishments had cesspools in which waste was stored. It was the night-soil men who would collect the waste. However, since they were paid to do so, some landlords, unwilling to pay, ignored the overflowing cesspools which then would accumulate in basements and adjacent areas. Yuk and yucky! The idea that bacteria and other filth were invisible in the contaminated waters was unknown to the people. They would collect the waste water, let the solids settle and then skim the liquid from the top believing this to be good for human consumption. Thus it is this part of London in which the cholera bacterium was spread among the citizens to infect many -- in the Garden Square neighborhood of Soho.
The main characteristic of the infection is severe diarrhea. Death comes from dehydration. What the bacterium does is multiply in the small intestine to form a mat on the inside walls of the intestine. The mat confuses the intestine to discharge fluid instead of taking in water to the body. As much as 30% of one's body weight is expelled from the gut during an infection. This then causes the body to compensate, especially the heart to pump harder and faster to push a decreasing volume of blood to the brain. If fluids are not replaced, the heart becomes overtaxed and eventually quits. It all started on August 28, 1854 when one little girl was stricken by cholera. She lived at 40 Broad Street in the Golden Square neighborhood. She vomited and passed watery green stool. Her mother rinsed her daughter's diapers in a bucket and then tossed the fouled water into the cesspool in front of their house. A leak in the cesspool caused the city well to become contaminated.
Cholera is spread by drinking fouled water, not by contact or aerosols. Thus when drinking water is contaminated with infectious sewage, the disease will strike those drinking the water. In this section of London, 70 persons died in one 24 hour period and it soon became a ghost town with few people coming and going. In 5 days, over 500 died. Those who could leave left the area.
Note that the bacterium (Vibrio cholerae) gets more virulent as it passes through multiple intestines so that a person can go from health to death within 12 hours!
In a systematic bit of detective work, a young physician, Dr. John Snow, was already studying cholera from a prior outbreak and found that it was not filth, poor living conditions, nor was it by contact that people contracted the disease. In studying water sources he noted that most of the deaths from the prior outbreak occurred in people living in south part of London, where the water supply was nearest where the city sewage was discharged. Yet, the mainstream medical establishment was fixated on the air as the transmitter of disease. Snow firmly believed it was the water, but needed to prove it. He examined the water, but nothing definitive could be found. Together with a scientist, William Farr, they began to determine the victim's sex, age, elevation from sea level, and where they got their water. He was in the midst of this research study when the Garden Square outbreak happened.
Snow began mapping the deaths and their proximity to different water sources in the area. At the end, nearly 700 deaths (in less than 2 weeks) were recorded of people living within 250 yards of the Broad Street water pump. Thus Snow was able to deduce the source of the outbreak by observing statistically unusual patterns that occurred during the outbreak. Snow's theory was challenged by Reverend Henry Whitehead. He started an inquiry into the outbreak to disprove the pump contamination theory. Whitehead, who lived in the neighborhood, was no less determined and persistent in investigating the outbreak. He had the advantage of knowing the community and getting more open input. Whitehead was able to piece together the picture that validated Snow's theory that it was the Broad Street pump that was the source of the outbreak. Snow developed a map of the neighborhood, its wells (pumps) and the deaths to graphically depict the outbreak. It is said that it was this map that helped Whitehead see the same pattern Snow did.
If you like a scientific detective story, history, challenging medical dogma, and systematic thinking, you should read this book. It was a joy!
© Baldwin H. Tom CMC
www.tbgroupconsultants.com
