'Poisonous air': how ignorance and prejudice helped the plague destroy millions of people
'11.06.2021'
Source: Lenta.ru report
The plague has firmly entered the history and culture of mankind as a monstrous disease from which no one could escape - even the doctors themselves. Pestilence penetrated homes, exterminated families, cities were filled with thousands of corpses. Now mankind knows the causes of the disease and methods of its treatment, but in the past, healers were powerless in the face of the Plague. Neither knowledge of astrology nor the study of ancient treatises written by ancient authorities helped. "Lenta.ru" talks about the plague pandemics and how they made humanity think about the real nature of infections.
Plague is one of the oldest diseases. Traces of its pathogen - Yersinia pestis - were found in the teeth of people who lived five thousand years ago, in the Bronze Age. This bacterium caused two of the deadliest pandemics in human history, killing hundreds of millions of people. The disease spread like a fire, destroying entire cities, and doctors could not oppose it, largely due to prejudice and a low level of medical knowledge. Only the invention of antibiotics and vaccines allowed mankind to defeat the plague, although it still occurs in various parts of the world, even in developed countries.
Inventive killer
The disease begins like a cold or flu: the temperature rises, weakness and headache occur. A person does not even suspect that the cause of his malaise was an invisible bacteriological bomb - a flea, whose insides are clogged with a plague wand. The insect is forced to burp the absorbed blood back into the wound, and an army of deadly bacteria gets into the body. If they penetrate the lymph nodes, then the patient develops a bubonic form of the disease. The nodes are very swollen. In the Middle Ages, they were burned and pierced - to the detriment of the patient himself and those who were nearby.
The septic form of the plague occurs when the plague stick enters the bloodstream, causing its intravascular coagulation. Clots disrupt tissue nutrition, and uncoagulated blood, penetrating the skin, causes a characteristic black rash. According to one version, it was precisely because of the blackening of the skin that the pandemic of the plague in the Middle Ages was called the Black Death. Septic plague is less common than other forms, but in the past mortality from it reached almost one hundred percent - antibiotics were not yet known.
Finally, the pulmonary form of the plague is what distinguished the Black Death. During the first pandemic - the Justinian plague - there was almost no mention of hemoptysis, but in the Middle Ages this symptom was just as common as buboes. Bacteria penetrated into the lungs and caused pneumonia, and the patient exhaled a plague bacillus, which fell into the respiratory organs of other people. During the Black Death, the disease was transmitted from person to person and did not need fleas as carriers.
In the past, getting a pathogen into the lungs almost always meant an inevitable death - without adequate antibiotic treatment, a person died in two to three days. It is the pulmonary form that is responsible for the death of tens of millions of people in the XNUMXth century.
Waves of death
Three major plague pandemics are known. Justinian's plague, which began in 541 AD, killed about one hundred million people around the world in two centuries and destroyed half of the population of Europe. The black death - the second wave of the disease - raged for two decades and claimed the lives of, according to various estimates, from one hundred to two hundred million people, which makes it the deadliest non-viral pandemic in the history of mankind. The third pandemic, which began in China and lasted about a century (from 1855 to 1960), killed more than ten million people.
The history of the plague began ten thousand years ago, when the soil bacteria Yersinia pseudotuberculosis, which is relatively harmless to humans, causing only a mild upset of the gastrointestinal tract, acquired several mutations that allowed it to colonize the human lungs. Then, changes in the Pla gene made the bacterium extremely toxic: it learned to decompose proteins in the lungs and multiply throughout the body through the lymphatic system, forming buboes. These same mutations gave her the opportunity to be transmitted by airborne droplets. As in many cases, epidemics are caused by close contacts between people and wildlife.
About four thousand years ago, mutations occurred that made Yersinia pestis highly virulent, capable of being transmitted by fleas through rodents, humans, and other mammals. Blood-sucking insects parasitizing mammals moved long distances along with travelers. Fleas climbed into luggage and merchandise, so the development of trade has become one of the causes of the pandemic. The Justinian plague originated in Central Asia, but through trade channels it first entered Africa, and from there it reached Byzantine Constantinople - a densely populated city and world center of the first millennium AD. At the peak of the epidemic, the bubonic and septic forms of the disease killed five thousand inhabitants a day.
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Black strain caused another strain of plague bacillus, which is not a direct descendant of the pathogen Justinian plague. It is believed that one of the implications of the pandemic was the Mongol conquests in the XNUMXth century, which caused a decline in trade and agriculture, and then famine. Climate change also played a role, when prolonged droughts led to mass migration of rodents, including marmots, closer to human settlements. Because of the crowding of animals, an epizootic arose - an analogue of the epidemic in animals.
Since groundhog meat was considered a delicacy, the spread of the disease among humans has become a matter of time.
The plague first hit Asia, the Middle East, Africa, and with merchant ships penetrated Europe, where it killed, according to approximate estimates, 34 million people.
The third pandemic began with an outbreak of bubonic plague in China in 1855, after which the infection spread to all continents except Antarctica. The natural site was located in Yunnan, which still carries an epidemiological threat. In the second half of the XIX century, the Chinese began to settle in this area in order to increase the extraction of minerals, for which there was a high demand. But this led to close contacts of people with yellow-chested rats, which were inhabited by plague-infected fleas. The growth of the urban population and the emergence of busy transport routes paved the way for the bubonic sea. From Hong Kong, the plague came to British India, where it killed one million people, and over the next thirty years - 12,5 million.
Dangerous prejudices
As in the case of other pandemics, the spread of the plague was promoted at the time by misconceptions about the nature of infectious diseases. For medieval doctors, the authority of the ancient thinkers of Hippocrates and Aristotle was undeniable, and a thorough study of their works was mandatory for all those who were going to connect their lives with medicine.
According to the principles of Hippocrates, the disease occurs due to natural factors and human lifestyle. At one time, this idea as a whole was advanced, since before Hippocrates, illnesses were usually considered the results of the intervention of supernatural forces. However, the ancient Greek physician had scant knowledge of the anatomy and physiology of man, so he believed that in order to recover the patient, it was necessary to properly care for him, so that the body itself could cope with the disease.
Medieval university graduates were the least experienced in treating illnesses, but had a high status and authority. They knew little of anatomy, and surgery was considered a dirty craft. Religious authorities opposed autopsy, so in Europe there were very few universities where they paid attention to the structure of the human body. The fundamental medical principle was the theory of humors, according to which human health depended on the balance of four fluids: blood, lymph, yellow bile and black bile.
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Most medieval theoretical physicians believed in Aristotle’s principle that miasma, a vapor that made the air “bad,” caused the plague. Some believed that miasms are formed due to the unfavorable location of celestial bodies, others blamed earthquakes on everything, wind from swamps, disgusting smells of manure and decaying corpses. In one of the medical treatises of 1365, it was argued that the plague could not be cured without knowing the humoral theory and astrology, which are very important for the practitioner.
All preventive measures to combat the plague were reduced to the elimination of toxic air that supposedly came from the south. Doctors recommended building houses with windows to the north. Sea coasts should also be avoided, because the fact that plague outbreaks began in port cities did not escape the attention of medical authorities. Only they could never have imagined that the disease spread through trade routes, and did not hover in the sea air. In order not to get the plague, supposedly you need to hold your breath, breathe through the tissue or burn fragrant herbs. Perfumes, precious stones and metals, such as gold, were used against the disease.
It was believed that the buboes contained plague poison, which must be removed. They were pierced, cauterized, ointment was used to drain the poison, but bacteria were released that could infect others. Despite the fact that the doctors took what they seemed to take all the necessary protective measures, many of them died. Others, realizing that their treatment was ineffective, followed their own advice and fled from the cities, although the plague overtook them and away from the foci. Contrary to the fact that the plague demonstrated the complete impotence of medieval medicine, the doctors soon overcame their dependence on ancient authorities and turned to their own observation and experience.
New era
One of the few effective methods (albeit with varying success) was quarantine, despite the constant protests of freedom-loving citizens and merchants. In Venice, a delay was set for ships to enter the port, which lasted 40 days (the word "quarantine" comes from the Italian quaranta giorni - "forty days"). A similar measure was introduced for people arriving from plague-infected areas. City councils began hiring doctors - plague doctors - specifically to treat the disease, after which they also went to quarantine.
As many leading theorists died in the wake of the pandemic, discipline was open to new ideas. University medicine failed, so people began to turn more to practicing specialists. With the development of surgery, more attention has been paid to the direct study of the human body. Medical treatises began to be translated from Latin into languages accessible to a wide audience, which stimulated the revision and development of ideas.
In general, the pandemic has contributed to the development of health systems.
The true cause of the plague - Yersinia pestis - was discovered only a few centuries after the Black Death. This was helped by the spread among scientists of Louis Pasteur's advanced ideas, which in the XNUMXth century turned its views on the causes of many diseases. The scientist, who became the founder of microbiology, was able to prove that infectious diseases are caused by microorganisms, and not miasma and disturbance of the body’s balance, as contemporaries continued to think, including his teacher and colleague Claude Bernard. Pasteur developed treatments for anthrax, cholera and rabies and founded the Pasteur Institute, which has now become a center for combating dangerous infections.
