Outbreak! Plagues That Changed History

by Bryn Barnard

  Walter Reed and Jesse dead

  In 1900, during the Spanish-American War, the mystery of yellow fever was finally unraveled. Thousands of American soldiers engaged in the conquest of Cuba had already died from yellow fever when a medical team led by Major Walter Reed arrived to try to determine the cause of the disease. Reed joined three other physicians already at work in Cuba: Jesse Lazear, Aristides Agramonte, and James Carroll. Lazear believed in Carlos Finlay’s mosquito-transmission idea. Reed was dubious but allowed Lazear to test the hypothesis. Carroll volunteered to be bitten by a mosquito that had fed on a yellow fever patient. He got sick and recovered. Needing further proof, Lazear allowed himself to be bitten. Two weeks later, he was dead. On October 23, 1900, Walter Reed announced that the Aedes aegypti mosquito was the insect vector (transmitter) for yellow fever.

  In Cuba, once the mosquito vector was confirmed, Major General William Crawford Gorgas was charged with its destruction on the island. The female Aedes mosquito prefers the moist edges of artificial water containers to lay her eggs. The casks of drinking water taken on board slave ships departing from Africa had transported Aedes to the Americas. Now ponds, flower vases, old tires, and other water containers were sustaining the disease. Soldiers under Gorgas’s super-vision emptied or smashed water containers and sprayed oil on ponds where Aedes might breed. Within five months, these methods had eliminated yellow fever from Cuba. Gorgas was a hero. In 1904, he was dispatched to the American revival of the Panama Canal project. By 1906, using the same methods, Gorgas had eradicated yellow fever there, too.

  It would not be until 1927 that the South African physician Max Theiler and his colleagues would prove that yellow fever was caused by a Flaviviridae virus and eventually develop a successful vaccine. Called 17D, it is still used today. Later, scientists learned where yellow fever hid in between epidemics: the African virus has found a permanent reservoir in the New World tropics among populations of tree-dwelling monkeys and their mosquito parasites. High above humans in the forest canopy, the virus cycles between insect and animal. As long as the forest is undisturbed, yellow fever remains “silent” for years or even decades. But each time a tree is cut to clear more land for habitation or agriculture, yellow fever may crash back to earth, ready to reenter the human population chain.

  The Flaviviridae virus

  But what about yellow fever’s impact in the white man’s grave? Africans suffered from the disease but were not insensitive to its deadly effects on their colonial masters. While whites saw yellow fever as an obstacle to control, Africans recognized it as an ally in their struggles for freedom and independence. Well into the 1980s, these words were still chanted by many African schoolchildren: “… Only mosquito can save Africa. Only malaria can save Africa. Only yellow fever can save Africa.”

  The African Flaviviridae virus has found a permanent reservoir in tree-dwelling New World primates, like these howler monkeys, and their mosquito parasites. When the tropical rain forest is cut down, the pathogens of the canopy may come into contact with people, giving yellow fever a chance to reenter the human infection chain.

  Repeat after me

  You know the drill: wipe, wash, don’t forget to flush. We learn the habits of personal hygiene from our parents, in school, on the job, and from the media. They seem basic, natural, obvious—even scientific. But they didn’t start that way. A little over a century ago, cleanliness and sanitation were still radical notions resisted by just about everyone. It took several global pandemics to change people’s habits.

  In 1817, a new disease swept out of India. It caused a violent, gushing diarrhea and vomiting that within a few hours could turn a healthy human being into a shriveled, blue-tinged corpse. No one knew what caused the illness. No one understood how it was spread. What people did know was that it didn’t discriminate: rich or poor, anyone who contracted the disease was likely to die. In seven separate pandemics over 180 years, it traveled to every continent except Antarctica, killing millions of people. Along the way it was given many names: hyperanthraxis, spasmodic cholera, Asiatic cholera, convulsive nervous cholera, cholera asphyxia, malignant cholera, the blue cholera, the blue fever, the blue vomit, the yellow wind, the plague, the pestilence, the black illness.

  Today we call it simply cholera. Simply put, it has been one of the most influential diseases of modern times. Cholera highlighted the desperate poverty and ghastly living conditions of newly industrialized Europe and America. It laid bare the threads connecting poverty to wealth. It settled the argument between two contending theories of disease, miasma and contagion. Most importantly, it catalyzed the development of modern sanitation, which enabled huge numbers of people to live together in close quarters and remain healthy, making the modern city possible. Sanitation is also partially responsible for the human population explosion. About one billion people inhabited our planet in 1800. We’re over six billion and counting today.

  Feeling blue

  For most of the nineteenth century, people didn’t know what caused cholera. Miasmists—followers of the ancient theories of Galen—blamed the disease on mysterious emanations: electrical currents (“the miasmic electric effluvium”), rotting garbage, foul-smelling sewers, and puzzling swamp vapors. Contagionists believed cholera was spread by contact with an infectious agent: bad cucumbers, bad beer, foreign food, shellfish, phosphorus, copper, sulfur, or other contaminants.

  Nineteenth-century industrial cities were fetid sties, mounded with garbage and human waste. Rivers served as both sewers and sources of drinking water, spreading cholera and other diseases. People died at rates rivaling those associated with the Black Death.

  Cures and preventatives were varied and contradictory. Several towns tried quarantines. Others experimented with noise: cannons were blasted, muskets fired, gongs banged, and shouts raised from sunrise to sunset. Several nations tried closing their borders to all travelers. Many individuals tried waist-hugging flannel cholera belts. Entrepreneurs made fortunes selling cholera brandy and cholera drops. Doctors prescribed hot poultices of salt, mustard, roasted black pepper, powdered ginger, scraped horseradish, or burnt cork. They also recommended ice-water baths, boiling-water baths, tobacco enemas, opium suppositories, and the ever-popular phlebotomy. England twice tried a National Day of Prayer and Deliverance. Nothing worked.

  The price of empire

  We can blame the British for the spread of cholera. Like other empires before them, the British invaded and connected areas that had previously been isolated from one another. Cholera is endemic to India, killing unnumbered thousands in repeated epidemics since at least 400 B.C. It even has its own goddess on the subcontinent, Hulka Devi. The first cholera pandemic began in 1817, when Britain was in the process of conquering the subcontinent. British soldiers stationed near Calcutta contracted cholera and carried the disease across the Himalayas to the Nepalese and Afghans they were fighting along India’s northern border. From there, cholera was relayed overland to Burma and Thailand and by sea to Sumatra, Java, China, Japan, Malaya, the Philippines, and Arabia. Slave traders carried the disease south from Oman to Zanzibar. It also migrated up the Persian Gulf to southern Russia. In each of these regions, thousands, sometimes tens of thousands, died in a matter of days. The winter of 1823–24 halted the advance.

  The second cholera pandemic started in Bengal in 1826. By 1830, cholera had reached Moscow. By September 1831, the disease was in Islam’s holiest city, Mecca. (It became one of the established dangers of the Muslim pilgrimage, reappearing forty times between 1831 and 1912.) That same year, it reached Berlin and Hamburg.

  Cholera became one of the established dangers of the Muslim pilgrimage, reappearing forty times between 1831 and 1912, until strict sanitation, vaccination, and quarantine were practiced. Here, cholera victims are unloaded at the port of Jaffa.

  A strict quarantine might have stopped cholera there. But in England, nothing was supposed to stand in the way of the free exchange of goods and services. Businessmen thwarted
an attempted quarantine to keep out ships that had visited infected German ports. Soon cholera started sickening people in the English town of Sunderland. Again, business interests argued against quarantine: it would hurt profits, it would cause unemployment. Sunderland was reopened. Cholera spread through England and Ireland, then jumped the Atlantic to North America. Again, tens of thousands died.

  Drink up

  We now know something that nineteenth-century people did not: cholera is spread by contaminated water. A look at living conditions in that era helps explain cholera’s global reach. In England, for example, the population was at an all-time high. People were pouring in from the countryside to towns and cities in search of higher wages. Thousands of workers were jammed into cramped, dark, poorly ventilated housing. Why dark? Since 1696, the Window Tax imposed a duty on dwellings with more than six windows. Clear glass was a luxury. To show off their wealth, the super-rich demanded homes with as many windows as structurally possible. Landlords, on the other hand, and even some members of the middle class, installed few windows. They even bricked over windows in some buildings to stay below the taxable number. People rarely washed their hands in those days, and in their gloomy, stuffy homes, they couldn’t see well enough to clean.

  Sanitation was inadequate to nonexistent. Although flush toilets had been used in England since at least the sixteenth century (Queen Elizabeth I got hers in 1597), most human waste was disposed of in pit outhouses. A landlord might provide one over-burdened, rarely emptied privy to serve thirty families. When it overflowed, fecal matter was deposited elsewhere: in cellars, in ditches, or in the street. In London, human waste would eventually end up draining into the Thames River, a malodorous sewer nicknamed “the Big Stink” that was also the final repository of butchers’ offal, tannery effluent, and household garbage. It was the city’s main source of drinking water.

  Under such conditions, disease was rampant. Aside from cholera, people suffered from “summer diarrhea” and epidemics of waterborne typhoid, lice-borne typhus, tuberculosis, influenza, and more. People died at rates not seen since the Black Death. Cities needed a continuous flow of new people from the relatively healthy countryside just to keep their population level. No wonder large families were encouraged.

  Death rates were highest among the poor. They ate bad food and got little of it. They lived in small, poorly constructed, hard-to-heat dwellings awash in human waste. They wore the theadbare castoffs of their betters. Ill-fed, ill-housed, and ill-clothed, their immune systems compromised, it is no wonder the poor died young. Britain’s upper classes assured themselves that this grotesque disparity was divinely ordained. Poverty was not an economic or social problem but a spiritual condition, a punishment for sin. With the passage of the 1832 Anatomy Act, poverty also became, in effect, a crime. Postmortem dissection by surgeons, anatomists, and medical students, formerly a punishment inflicted only on the very worst condemned criminals, now became instead the fate of paupers unable to pay for their own burials. The Poor Law Amendment of 1834 tightened the noose, outlawing cash charity to the unemployed poor and forcing them into the prison-like workhouse—even orphans, the elderly, and the disabled.

  Edwin Chadwick, a reforming civil servant, documented the conditions affecting the poor with his Report on the Sanitary Condition of the Labouring Population of Great Britain, presented to Parliament in 1842. Chadwick asserted that the squalid existence of Britain’s poor was involuntary. He compared it unfavorably to American slavery. Chadwick also revealed that country people lived longer than townsfolk. In a city like Leeds, laborers could expect to die, on average, at age seventeen. Tradesmen died in their mid-twenties. Even the privileged gentry usually survived only into their forties. You might make more money in a city, but you wouldn’t live long to enjoy it.

  Next they’ll want health insurance

  Chadwick, who lived to be ninety, thought this a waste. He was an advocate of utilitarianism, the belief that government should act to create “the greatest happiness of the greatest number.” He argued that better living conditions would allow poor people to work harder and be less of a burden on society. Chadwick was also a miasmist. He declared that “all smell is disease.” Get rid of the smell, Chadwick reasoned, and you get rid of the disease. He recommended improved housing, paved streets, clean drinking water, flush toilets, and efficient sewers for everyone. Opponents called this “mawkish philanthropy,” but after years of bickering and thousands more cholera deaths, Parliament began to implement Chadwick’s reforms with the first Public Health Act of 1848. The Window Tax was repealed in 1851. The third cholera pandemic started in 1853, killing fifteen thousand people in England alone. It helped spur the Sanitary Act of 1866, the second Public Health Act of 1872, and the third Public Health Act of 1875.

  Check out the apron on that guy

  Just as important as Chadwick in the prevention of cholera was Ignaz Semmelweis’s advocacy of hand washing. In 1846, Semmelweis was a Hungarian obstetrician working in Vienna. It is hard to believe now, but in those days even well-off Europeans rarely washed their hands. No wonder: not all homes or businesses had piped-in water, and hot water had to be heated on a stove. With knowledge of microbial pathogens still in the future, the need for regular, systematic hand washing wasn’t understood. Semmelweis, however, pointed out that women who gave birth with midwives (or even on the street) had a much better chance of survival than those who delivered their babies in crowded hospitals, where doctors worked ungloved and wore the same attire throughout the day. For surgeons, bloody aprons were a sign of professional prowess—the redder the better. Semmelweis suggested that physicians were passing a fatal “something” from sick and newly dead patients to healthy mothers. Although doctors were incensed at the accusation that they were contagious, Semmelweis ordered his subordinates to wash their hands in chlorinated water before entering his wards. The maternal death rate dropped from 30 percent to 1 percent. The Semmelweis technique spread from hospitals to businesses, schools, and homes as a cheap, effective way to stop illness. It still is.

  Ignaz Semmelweis introduced modern hand washing into his maternity wards. He dropped the death rate from thirty out of a hundred to one.

  Though the Chadwick reforms and the Semmelweis method improved urban life expectancy and helped curb cholera, the disease remained a huge health problem. In 1854, a London physician named John Snow noticed that in Soho many cholera deaths were concentrated around the Broad Street public pump. To see if water pollution was the cause, he removed the handle so that the pump could not be used. Neighborhood cholera deaths plummeted. Eventually Snow compiled a detailed survey of the many competing companies that supplied water to London, each with its own overlapping systems of pipes. He conclusively connected cholera with the sewage-contaminated drinking water of one company, drawn downriver from London. More investigation showed that of London’s eight private water companies, only five filtered their water. (One customer found his pipes clogged by a rotting eel!) Snow was attacked for his ideas by miasma-obsessed sanitationists, who feared his focus on waterborne contagion would slow the cleanup of the English slums. But by 1902, London had merged its private water companies into a single municipal corporation that supplied everyone in the city with filtered, chlorine-treated water. Cholera and other waterborne diseases faded. Health improved.

  These changes were noted and copied elsewhere. In Germany, renowned pathologist Rudolph Virchow designed a new sewer system for Berlin. In the United States, Dr. John H. Griscom adapted Chadwick’s theme and title for his influential 1845 tract, The Sanitary Condition of the Laboring Population of New York. Jacob Riis’s 1890 blockbuster, How the Other Half Lives, also helped ignite American reform. Across Europe and America, and later Japan and other parts of the industrializing world, cities were transformed from fetid sties to livable metropolises with improved housing, efficient sewers, clean piped water, and regular garbage removal.

  To understand the importance of these changes, one has only t
o look at the fate of an industrial nation denied the basics of modern life. Iraq is an instructive example. Though the dictator Saddam Hussein ruled Iraq for much of the late twentieth century, the country was modern and prosperous, with a large, educated middle class concentrated in cities like Baghdad, Fallujah, and Basra. In the 1990s, however, the United Nations implemented sanctions that denied Iraq critical water treatment system parts and medical supplies the Iraqi government might have also been able to use to manufacture weapons. The health effects were immediate, widespread, and ghastly. Infant mortality rose sharply. Infectious diseases spread. Cholera returned. In all, about a million Iraqi children died. Any other industrial country denied essential modern sanitation would suffer a similar outcome.

  Have vibrio, will travel

  Thirty years, two cholera pandemics, and hundreds of thousands of deaths after John Snow’s observations, the great German biologist Robert Koch finally discovered the microbe responsible for cholera. In 1883, during the fifth pandemic (1881–86), Koch beat his archrival, Louis Pasteur, by identifying the cholera vibrio in the disease’s homeland, India. Koch became a German national hero. (Vibrio is one of the many shape-based words still used to describe bacteria. A vibrio is comma-shaped. A bacillus is rod-shaped. A spirochete is screw-shaped. A coccus is round.)