Cholera: Tracking the First Truly Global Disease
National Geographic Channel
|June 14, 2004|
A new and terrifying disease struck England in October of 1831 and quickly spread across the kingdom. Over the next two years, thousands died from this mysterious illness, so virulent that a person could be in good health at dawn and be buried at dusk.
Citizens lived in terror, sealing their doors and windows at night against the feared "night air." There was no cure.
Symptoms began with vomiting, diarrhea, and fever, which violently dehydrated the body: Soon the patients' skin turned bluish grey, they began to writhe with muscle spasms, their eyes sank in their sockets, and they grew cold as their pulse flickeredand vanished.
The disease was Asiatic cholera, also known as spasmodic cholera of India, its place of origin. A huge epidemic in Bengal in 1917 first drew the attention of European physicians.
Over the next decades, cholera spread widely over trade routes, becoming the world's first truly global disease, infecting people from China to the Middle East and from Europe to the United States.
A second epidemic struck England in 1848 to 1849, killing between 50,000 and 70,000 in England and Wales. A third outbreak in 1854 left over 30,000 people dead in London alone.
Doctors understood little about this horrible illness, but tried, often in vain, to save their patients with anything from laudanum (an opium tincture) and brandy to blood letting.
"The cholera," said the British Annual Register for 1932, "left medical men as it had found themconfirmed in the most opposite opinions, or in total ignorance as to its nature, its cure, and the causes of its origin, if endemicor the mode of transmission, if it were infectious."
Grim Living Conditions
It was indeed infectiousand grim, urban living conditions fueled its spread. With the rise of the industrial age, lack of work in rural English villages prompted large migrations to cities.
In the first half of the 19th century, London's population soared to 2.5 million people. The city had become one of Europe's trading and manufacturing capitals, producing everything from woolen cloth to weapons. Families flocked to urban centers along with their livestock, often living eight or nine to a room beside their animals in tenement buildings.
Cities lacked the infrastructure needed to contend with the ever growing masses. As the population swelled, so did the pestilential odors that rose from the over 200,000 cesspools across the city and from the sewage that piled up in every ditch and alleyway. The sewage overflowed into houses and marketplaces from storm-water sewers during the frequent rainstorms and at the River Thames's high tide, said Jon Schladweiler, a historian with the Arizona Water and Pollution Control Association.
Much of this waste eventually made its way into streams or directly into the Thames. In England rivers were viewed as a waste-disposal system, and the Thames became a reeking brown sewer. This scenario was pervasive across Europe. "Disease, stench, and filth were rampant in cities throughout Europe at the time," Schladweiler said.
There was a lot of confusion about the disease, as in the early days of HIV, said Ralph Frerichs, professor of epidemiology at University of California, Los Angeles. Most physicians believed the disease was contracted by breathing noxious vapors, or miasma. "There was a lot of fear, because people can't stop breathing air," Frerichs said.
But one doctor, John Snow, published another theory in 1849: Cholera was transmitted by contaminated food or water. He argued that it couldn't be airborne because it didn't affect the lungs. But his theory was ignored, attacked by many among the medical profession because he couldn't identify the "poison" in the water.
It wasn't until the 1854 outbreak that Snow was able to prove his argument. He mapped the location of cholera deathsand found high concentrations in certain areas. For example, about 500 people died in ten days near the intersection of Cambridge and Broad Streetsthey shared a single water supply.
He went to city officials with his data. "He was very concerned about transmitting this information to the public and the Board of Guardians," Frerichs said. The board, a city-council-like body, was in charge of public health, welfare, and sanitation. The pump handle from the water source was removedand cases in the area dropped to almost none.
At that time two companies supplied the city with water from the Thames, one located upstream, the other, downstream. Snow discovered that cholera was rampant among patrons whose water originated downstreamcontaminated by city sewage.
The Water Act of 1852 required that water companies filter water. In 1866 Charles Greaves, the engineer from the East London Company, admitted that water from open reservoirs and the river had been pumped directly to the city without purificationthough company officials later denied it. That year 4,500 people died in East London in the country's fourth cholera epidemic.
The Great Stink
By the summer of 1858, the metropolis was wrapped in "The Great Stink." The stench from the Thames had grown so intense that thousands of residents fled the city.
Windows of the Parliament building had to be covered with curtains soaked in chloride of lime to keep the government openbut Parliament ultimately closed down because the smell became unendurable. "This was one of the few times in history it's closed," Schladweiler said.
The repeated outbreaks of disease and unbearable odors prompted city officials to build new drains, protect the water supply, construct public bathhousesand construct proper sewers.
The sewer-building project, designed by engineer Joseph Bazalgette, linked 1,000 miles (1,600 kilometers) of street sewers to 82 miles (132 kilometers) of huge, egg-shaped sewers that fed effluent out into the open sea. This new shape kept sewage flowing, even in flat landscapes like the Thames River Valley.
With better sanitation, the cholera epidemics stopped. In 1876 the comma-shaped bacterium was discovered under a microscope by the German doctor Robert Koch. Cholera was then fully recognized as an acute bacterial infection of the intestine caused by the intake of food or water contaminated with Vibrio cholerae, usually from human feces.
Bazalgette's novel design was adopted by city planners across Europe and in the U.S. Though it had to be prompted by epidemic disease and crowded, pestilential slums, England became the leader in the sciences of urban planning and public health.
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