Cholera Epidemics: Five Pandemics in the Nineteenth Century

Overview

During the nineteenth century, five cholera pandemics swept through India, Asia, Europe, and North America, infecting huge segments of the population and killing millions of people; a pandemic is defined as an epidemic encompassing a wide geographical area. Millions more would undoubtedly have perished were it not for the work of Doctors John Snow (1813-1858) and Robert Koch (1843-1910), whose research helped isolate the cause of the disease. Their discovery of the link between cholera and poor sanitation practices would forever change public health policies in Europe and North America.

Background

For centuries the deadly cholera disease festered on the Indian subcontinent. As early as 2,500 years ago, Sanskrit writings tell of the spread of an illness similar in symptoms to cholera. In 1503 the explorer Correia reported that 20,000 men in the army of the Sovereign of Calicut came down with a "disease, sudden-like, which struck with pain in the belly, so that a man did not last out eight hours at a time." Over the next 300 years, epidemics would periodically emerge and spread throughout India and the East, but it was not until 1817 that the world would come to know the devastating effects of cholera.

In that year, outbreaks erupted in several Indian provinces. Among the first victims were soldiers in the English army barracks of Fort William in Calcutta. Once the men were infected, the onset of the sickness was rapid—and painful. Victims would experience vomiting and severe diarrhea, accompanied by terrible cramps. Their bodies would soon dehydrate, and death would often occur in the space of hours. Within weeks, 5,000 British soldiers had succumbed to cholera.

The sickness quickly spread throughout India. Over the next several months, 25,000 of Calcutta's residents were treated for cholera—4,000 died. By 1818 it had moved across India, striking an estimated 7.5% of the exposed population. Now, for the first time, the disease escaped the continent. With the advent of new roads, railroad tracks, and faster ships, it spread like wildfire. Over the next three years cholera was carried by merchant ships to China, Japan, and Southeast Asia. Pilgrims traveling to and from Mecca spread the disease throughout the Arab world. By 1821 it had invaded Java and Persia. In 1823 Egypt and Syria fell victim. Thus began the first cholera pandemic.

In 1824 another epidemic outbreak of cholera developed in India's Ganges Delta. By 1829 it had moved through Persia and to the shores of the Caspian Sea. In that same year, it expanded north and west into Russia, where the Russian army carried it into Poland. In 1831-1832 it reached England and France. Within 18 days of its arrival, the French reported at least 7,000 deaths. Next, cholera crossed the Atlantic by way of immigrants, infecting thousands in Canada and the United States.

By the end of the nineteenth century, three more major pandemics would make their way around the world, spreading the disease across Europe, North America, India, and Asia. By the end of the century, millions would lose their lives.

Impact

In 1831, during the second pandemic, cholera reached the shores of England. In the port town of Sunderland, old man Sproat, aged 60, and the young, healthy William Sproat, Jr., were among the first to die. Doctors from around the country descended on Sunderland, trying to ascertain a cause. Their diagnosis—the victims were either old and feeble, or predisposed to sickness. Although local coal merchants and traders warned that cholera was being carried to England on ships from India, the doctors disagreed. They firmly believed that it was not contagious.

At that time, a young doctor named John Snow was beginning his career as an apprentice in Newcastle-on-Tyne. He watched as patients continued to come down with the symptoms of the disease, and was horrified by what he saw. When cholera recurred in 1848, Snow began to chronicle its spread. He carefully followed its origination in India and the path it took westward, towards London and Paris. In 1849 he published a pamphlet entitled On the Mode of Communication of Cholera, which outlined his belief that poor sanitation and unclean water were directly linked to the epidemic.

During the nineteenth century, sanitary conditions in the world's big cities were abysmal. The Industrial Revolution had led to the growth of urban tenements, where fresh water was hard to come by and sewers were simply elongated cesspools. Refuse was shoveled by hand, and barrels of excrement were often thrown outside, even flung from open windows. London got much of its water from the polluted Thames River or from filthy wells. A neighborhood of 20 to 30 families would draw their water from a single pump two or three times a week. If the pump was not working, they would often reuse unclean water.

In the mid 1850s Snow carried out a detailed investigation of the cholera epidemic. He was able to demonstrate that over 500 cases in central London could be traced to a single source—a public well known as the Broad Street Pump. Everyone who drank the water was coming down with the disease. He asked local authorities to remove the pump handle, and as soon as they complied, cholera quickly disappeared from the area. Snow soon traced other outbreaks to the Thames and to other polluted wells. He reached the conclusion that the disease was being transmitted from person to person through the water supply. He found that the water was being contaminated by untreated sewage tainted with the cholera virus, which permeated the ground and polluted wells. Snow's discovery of the link between contaminated water and cholera created a model for the understanding of disease transmission, and was the first step leading to a public understanding for the need for proper sanitation. But the actual cause of the disease was not discovered until many years later by the German bacteriologist Robert Koch.

In 1884, while examining Calcutta's water supply, Koch observed a unique, comma-shaped bacteria. When he examined the fecal matter of 70 people who had died of cholera, he found the same bacteria in all of the victims. For the first time, he was able to isolate the exact cause of death as the Vibrio cholerae bacteria, or cholera.

Koch confirmed Snow's water-cholera relationship hypothesis, and discovered that the disease was ingested by victims, either from fecalinfected water, or through eating shellfish, vegetables or fruits onto which flies had dropped infected human fecal matter. From his research, doctors learned of the necessity to isolate cholera victims in order to stem the spread of the disease.

More importantly, once the link between sanitation and cholera was established, the way was paved for public health policies, which had not previously been in existence. In the 1840s the General Board of Health was established in England, calling for better methods of refuse collection, new sewers, and the destruction of slums. The Public Health Bill of 1848 set up a central authority to ensure that homes had proper drainage and that local water supplies were clean. When cholera struck that country for the third time in 1868, improvements in the water system led to far fewer infections.

England's success was recognized by governments around the world. In New York City, where a large immigrant population had brought the disease in, a health board was created and port quarantines were enforced. The U.S. federal government soon created a Public Health Service, as did governments throughout North America and Europe. Water and waste systems continued to improve throughout the century, and in the 1890s when cholera struck the world for the fifth time, those continents remained virtually unscathed.

The discovery of a treatment for cholera, however, took much longer. In 1830 the German chemist R. Hermann first discovered that a change in the blood's fluid balance had an effect on cholera excretions. But it wasn't until the early 1900s that the replenishment of water and salt was used to cure the dehydrating effects of the disease.

The cholera pandemics of the nineteenth century had a devastating effect on much of the world. Britain lost an estimated 130,000 people over the course of five epidemics. In India, cholera claimed more than 25 million lives from the 1800s to the early part of the twentieth century. Although modern sanitation and advancements in the treatment and prevention of cholera have reigned in the disease, the risk is far from over. The World Health Organization (WHO) estimates that 78% of the population in underdeveloped countries is without clean water and adequate waste disposal. As recently as 1991 and 1993, epidemics raged through Central America and Southeast Asia. War, famine, flood, and the lack of clean water in developing nations keeps the risk of another outbreak ever present.

STEPHANIE WATSON