In 1817, the world learned of a new disease, cholera-an acute gastrointestinal disease that kills a person in one day. The home of the “cholera Vibrio” (Vibrio cholerae) is the Indian subcontinent located around the Bay of Bengal, where this bacterium lives in brackish water, moving in it with a single flagellum. However, scientists now know that the cholera Vibrio is actually a hybrid organism: a Vibrio that becomes more virulent after infection with the virus.
This confluence of virus and bacteria is likely to have occurred many times in the Bay of Bengal and beyond throughout history, but the spread of cholera outside South Asia was possible only after the advent of faster ships during the industrial revolution – first elegant sailboats, and then steamships.
In the 1820s, the disease penetrated through Afghanistan into Persia and reached the Caspian sea. When the cholera epidemic subsided, Europe and the Americas breathed a sigh of relief. However, in 1829 cholera crept out again, passed through Russia and Hungary and in 1831 arrived in Europe. The following year, she crossed the Atlantic ocean, hitting first Montreal and then new York. In 1834, the disease came to the Pacific coast.
The death rate from cholera was very high. Half the people infected with it died. The second pandemic killed 100,000 Hungarians and a slightly larger number of French. In American cities, cholera has killed five to ten percent of the population. According to one estimate, 150,000 Americans died from it.
Cholera continued to destroy the world in waves every ten years – in 1839, 1863 and 1881. However, it was not the only epidemic disease. Yellow fever (a disease caused by a mosquito-borne virus) has also periodically swept the United States and claimed as many, if not more, lives. In 1878 alone, the disease killed nearly 10% of the population of Memphis and Vicksburg. It was she who stopped the initial efforts to build the Panama canal.
For reasons that historians still struggle to explain, cholera inspired a new level of horror. “Cholera has United the world more than any other infectious disease,” writes Christopher Hamlin in Cholera: the Biography. “The fate of all people could be in the intestines of any person.” Perhaps the humiliation that accompanied death from cholera (vomiting, incessant loose stools, pale to blue skin), inspired Americans with such horror, what did not cause them any epidemic. A man who was healthy in the morning could die in the evening. However, yellow fever (which was called in Spanish el vómito negro — “black vomit”) treated its victims far from the best way. (The word “yellow” in the name of this disease is associated with the color of the flag, which was raised on ships if there were patients on Board.)
Probably, the foreign origin of cholera (which came from the East) played into the hands of hidden and growing fears of “strangers”: African Americans, newly arrived Irish Catholics and Jewish immigrants. Perhaps it evoked memories of the “black death” that had also come from the East centuries earlier. Or perhaps the authorities began to worry that cholera would provoke social unrest. In some European cities, when cholera appeared, riots broke out.
Whatever the cause, cholera hastened sanitary reforms. At the time, no one understood how the disease spread, but hygiene practices gained credibility on the battlefields. The experience of Florence Nightingale, first during the Crimean war and then during the organization of hospitals in the UK helped to substantiate the idea that cleanliness (clean bandages on wounds, cleaning garbage, washed floors) can stop the spread of diseases. American nurses brought home an equally instructive experience from the Civil war.
Meanwhile, new York realized that quick action by the authorities can nip the epidemic in the Bud before it gains momentum. In 1866, when cholera was once again ready to ravage the city, the newly formed city health Committee quarantined the steamer Virginia, which had sick passengers on Board. Doctors went from house to house, hospitalizing patients in dispensaries. Groups working around the clock reported new cases . Although none of these people understood how this intestinal disease spread, their intervention changed the situation for the better. Only 600 people died of cholera. Shortly before that, after cholera swept the country, American President Zachary Taylor urged citizens to observe fasting and pray for redemption . However, the authorities now understood that decisive action could stop the spread of the disease. Thus began a new era of health initiatives.
The old Croton aqueduct began supplying drinking water to new York city beginning in 1842. Water treatment plants were built in the 1890s. And George Waring Jr. (a mustachioed dandy who rode everywhere) organized a two-thousand-strong army of white-clad sanitation workers to keep the city clean. When Waring died in 1898 in Cuba of yellow fever, mourners called Him a “fever killer” and an ” Apostle of purity.”
The sanitary reforms were more effective than had been hoped. They are still held in the highest esteem. In 2007, the British Medical Journal conducted a survey in which participants called the “sanitary revolution” the most important of fifteen medical events over the past 170 years — even more important than antibiotics (2nd place in the ranking), vaccines (4th place) or microbial theory (6th place) . However, it is somewhat paradoxical that health reforms were carried out on the basis of misconceptions about the spread of diseases. These reforms were based on the “miasma theory”, which had its roots in Ancient Greece. Sanitary doctors believed that diseases arise under the influence of miasmas-disgusting smells emanating from swamps, cemeteries, sewers and even disturbed soil cover. Even George Waring Jr., who designed the advanced sewer system for Memphis, went to his grave believing that the microbial theory of disease was completely wrong.
By 1900, however, the previously unpopular microbial theory had become accepted. In the 1790s, an Englishman named Edward Jenner developed the first smallpox vaccine based on a related virus that infected cows. In the mid-nineteenth century, the Frenchman Louis Pasteur disproved the theory of self-generation, while developing protocols for sterilization and storage of food. He also created vaccines for anthrax and rabies. Meanwhile, in the 1880s, the German Robert Koch isolated the bacteria that cause tuberculosis and cholera, providing further evidence that certain microorganisms cause certain diseases. Suspecting that it was germs, not miasma, that did it, doctors Ignaz Semmelweis in Vienna and Joseph Lister in Edinburgh significantly reduced the mortality rate in hospitals through the introduction of simple disinfection protocols.
And in 1928, the scientist Alexander Fleming returned from a holiday to his London laboratory and found mold in Petri dishes designed to grow bacteria. His attention was drawn to the clean, bacteria-free area around the bluish spots. As a result, this mold brought the world the first antibiotic — penicillin. First tested on allied soldiers in the final years of world war II, penicillin subsequently became publicly available. Then were discovered the antibiotics were isolated from microorganisms of the soil, such as streptomycin, which, in contrast to penicillin, could cure tuberculosis.
Health reforms and a new understanding of disease based on microbial theory, vaccines and antibiotics have changed human existence. A person born in Western Europe in the middle of the XIX century could expect to live to 45 years . A hundred years later, life expectancy rose to 70 years. In 2000, women, who generally live longer than men, generally crossed the 80-year mark in all developed countries.
However, the average life expectancy gives a wrong idea of the true state of Affairs. The mortality rate has always been disproportionately high among the youngest people. Improved sanitation, vaccines and antibiotics have had the biggest impact on reducing child mortality. If you had four children in the nineteenth century, you could reasonably expect one of them to die within the first year of life, a victim of dysentery, measles, typhus, or a number of other diseases that are now easily treated (or vaccinated). To be sure, the mortality rate was higher in urban slums and among the poor, with some places close to half of all children.
In the mid-twentieth century, child mortality in the United States and Britain decreased by almost an order of magnitude . Only three of the 100 children born died within the first year of life. These days in Western Europe, only five out of 1,000 die before they are a year old. (In the US, this figure is slightly higher — seven per 1,000 newborns.)
Child mortality among modern hunters and gatherers, such as the kung tribe in South Africa or the ache tribe in South America, roughly corresponds to the level of child mortality in Europe before the modern era . About a quarter of children die at an early age, mostly from infectious diseases. In all likelihood, this pattern has been consistent throughout human evolution, making the “revolution in mortality” that has occurred over the past 160 years all the more remarkable. At last we have got rid of such eternal and terrifying element of existence as premature death of descendants.
The victory over infectious diseases was the culmination of a trend that began about 60,000 years ago, when humans first emerged from Africa and dispersed to other habitats. For better or worse, this event was an important step towards the domination of man on Earth. In Eurasia, the Americas, and Australia, man has encountered a vast abundance and wide variety of animals (such as mammoths, cave bears, woolly rhinos, giant wolves, huge sloths, and hippopotamus-sized wombats) that seems fantastic now. However, about 10,000 years ago, these animals, as well as Neanderthals (our hominid cousins), disappeared.
For thousands of years, Homo sapiens has left behind a trail of extinction. Even as our parasite population grew larger, we simplified the external ecosystem. With the advent of the microbial theory and the development of the sanitary movement in the nineteenth century, this undefined propensity to extermination entered a new phase. In the end, as diligently as we hunted the animals we liked to eat, we began to pursue the microbes and parasites that had fed on us from time immemorial. Perhaps in doing so we have created a biological innovation: the immune system, which in the process of evolution had to deal with a lot of very active satellites, for one or two generations suddenly found itself alone.