Humans had difficulty understanding that creatures that cannot be seen with the eyes cause deadly diseases, and believed that "bad air" causes them
Written by: Ariel Kers, Tamar Jordani, young Galileo
Often mistakes in science are harmless and even positive because they lead to the discovery of the truth. But in the case of disease-causing bacteria and viruses, these mistakes were fatal. In ancient times, scholars thought that infectious diseases - such as cholera and the Black Death (disease of the desert or smallpox) were caused by miasma.
What is miasma? The meaning of the word is "impurity" in ancient Greek, and it means "bad air" or poisonous vapors found near decaying organic matter and dirt. If the person is exposed to the "bad air", he will catch the disease. The signs of "bad air" were simply bad smells. The ancients were not very far from the truth: even today we know that poor hygiene, dirt and filth can bring diseases because they are a breeding ground for the development of bacteria. But even the wise philosophers or the first scientists did not imagine the existence of bacteria - mainly because they did not have a microscope and they never saw the ceaseless action of tiny creatures that can be seen in every drop of water.
The development of the first microscopes
The concept of miasma continued even in the Middle Ages and after. Its power was great even after the development of the first microscopes, in which it was possible to see that almost everything that exists is infested with tiny creatures in a variety of shapes and sizes. As did the Dutch scientist Anthony van Leeuwenhoek, who built microscopes himself and began to study the microorganisms he discovered with their help. When scientists such as the Frenchman Nicolas Andre proposed back in 1700 to test the assumption that those tiny organisms that cannot be seen without a microscope cause diseases that can be fatal - many despised it and ignored the proposal. Because how can such tiny and insignificant creatures, almost invisible, cause disease and death to the sublime man, the prince of creation? This erroneous and arrogant perception lasted until the middle of the 19th century and delayed for hundreds of years the acceptance of the theory of bacteria and viruses as disease-causing agents - and of course the appropriate treatment for them. Meanwhile, hundreds of thousands of people fell ill and died.
Not from the air, but from the water
In the end, scientists managed to correct the mistake. In the fifties of the 19th century, there were repeated outbreaks of the dreaded cholera disease in London and Paris. The doctors advised people, quite rightly, to maintain hygiene. Dr. William Parr, Deputy Director of the Census of London in 1851, was convinced that cholera was airborne because the pollution was very high near the River Thames, which runs through the center of London. What caused the pollution of the river? Huge amounts of garbage, dirt and leftovers that Londoners throw into the river and its banks. The acceptance of the wrong miasma theory delayed for a long time the discovery of the truth, which was proposed by other scientists - that cholera was transmitted by water, and not by air; And that whoever drinks this polluted water is doomed to get sick.
The bacteria theory is accepted
"Bad air" in Italian is mal aria, hence the name of the disease, which was widespread in Italy at the time - malaria, which today we know is also caused by microorganisms that are transmitted from a sick person to a healthy person through a mosquito bite. In 1854, the Italian scientist Filippo Pacini discovered the bacillus - a bacterium that causes anthrax (Hebrew: anthrax; an acute infectious disease) and food poisoning. But the miasma theory was very popular among the Italian scientists of that time, and therefore they simply ignored his discovery!
In 1876, the German scientist and winner of the Nobel Prize in Medicine, Robert Koch, conclusively proved that this bacterium causes the anthrax disease, thus putting an end to the miasma theory. At the end of the 19th century, the theory of germs as the cause of disease was finally accepted, and one of the results of this development was a better observance of the rules of hygiene in London and other large cities. Today, scientists know a lot about bacteria, viruses and microorganisms that cause diseases, and fight them with considerable success.
The invention of penicillin
In 1928, the Scottish physician Dr. Alexander Fleming was busy in his research laboratory at the university hospital where he worked in England. Ten years earlier, in the First World War, he served as a medical officer in the British army, where he was exposed to the harsh sights of wounded soldiers who died as a result of infections from open wounds. He used the years since the war to search for a substance that would kill bacteria on the one hand and not harm the patients' healthy cells on the other hand. Most of the antibacterial substances that were used until then caused damage to healthy tissues, and also attacked the cells of the patient's body.
That day in 1928, Fleming sat tired in his laboratory. He got up to organize the glass dishes with the food, in which he had grown colonies of bacteria that cause severe staphylococcal infections. Penicillium mold began to develop in one of the flasks, and Fleming had no choice but to throw it in the trash. But just before that he decided to look at the mold through the microscope. How great was his astonishment when he noticed that a ring free of bacteria had formed around the mold!
In the following days, Fleming devoted all his energy to a careful examination of the mold and found that a certain substance in it, which he named penicillin (after the type of mold), succeeds in effectively eliminating bacteria. In the next step, Fleming discovered that this wonderful substance does not harm the human body at all. The problem then was to produce the material in large quantities, as it was a long and extremely expensive process.
Fleming had no funding, but luckily a team of British researchers managed years later to continue Fleming's work and produce penicillin for everyone. The vital drug, which was the first antibiotic in the world, was used to treat many British and American soldiers in World War II and saved their lives from infection and death in agony. The revolutionary discovery born of a mistake earned Fleming a title of nobility and even the Nobel Prize for Physiology and Medicine, and he shared it with researchers Flory and Chen, who made penicillin a widely useful drug.
The article was published in the October 2014 issue of Young Galileo
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One response
Penicillin was not invented. Penicillin was discovered. You should fix the title.