How Fleming accidentally discovered penicillin. And why will the new antibiotics save only for a while?

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How Fleming accidentally discovered penicillin. And why will the new antibiotics save only for a while?
How Fleming accidentally discovered penicillin. And why will the new antibiotics save only for a while?
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Life before the discovery of antibiotics is difficult and scary to imagine. Tuberculosis and many other infections were often a death sentence. Fate endured them much more often than nowadays: more patients - the higher the chances of being infected. Any surgical operation was compared to Russian roulette. In the 1920s. American psychiatrist Henry Cotton, who presumptuously treated the mentally ill with organ removal, boasted that his technique was relatively safe: only 33% of his patients died. As it turned out later, Cotton was lying, and the mortality rate reached 45%. Hospitals were breeding grounds for infection (however, now little has changed, and the reason is precisely in antibiotics). Even an ordinary scratch could lead to the grave, causing gangrene or blood poisoning. Existing antiseptics were only suitable for external use and often did more harm than good.

An open window and a rotten melon changed everything

The discovery of antibiotics, more precisely, penicillin, is attributed to the Scotsman Alexander Fleming, but a few reservations must be made. Even the ancient Egyptians applied moldy bread soaked in water to the wounds. Almost four years before the accident in Fleming's laboratory, the antibacterial properties of mold were described by his friend André Grazia. Only Grazia thought that mold does not kill germs directly, but only stimulates the body's immune system, and injected it along with dead bacteria. What type of mold the scientist cultivated and what substance she secreted is unknown: Gracia fell seriously ill, and when he returned to work, he allegedly could not find old records and samples.

Mold in a dish with a bacteria colony. Transparent circles around the fungus - areas where bacteria have died

It was the mold that killed the staphylococci in Fleming's lab. It happened by accident: the spores of the fungus were blown out by the wind from an open window. Like Grazia, the scientist could not correctly determine which type of healing mold belongs to. He could not even isolate a substance that he called penicillin - in the experiments the Scotsman used a filtered "broth" where fungi grew. But Fleming described in detail how this filtrate affects various bacteria, compared mold with other species, and most importantly, he saved the samples and sent them out at the first request of colleagues.

One such sample was kept at Oxford University for almost ten years. In 1939, German immigrant Ernst Cheyne isolated pure penicillin from it, and his boss Howard Flory tested the drug on animals. In 1945, they and Fleming were awarded the Nobel Prize in Physiology or Medicine. Norman Heatley, who was in charge of the team for breeding mold and also invented a method for cleaning the antibiotic, was left without a reward, although his merit was no less. Suffice it to say that the first patient, a 43-year-old police officer with a face wound, had to filter his urine to extract the precious penicillin from it. He quickly felt better, but still there was not enough medicine, and a month later he died.

When Oxford scientists proved the effectiveness of penicillin, there was World War II. A reliable antibacterial agent was required more than ever: soldiers died more often from infections carried into wounds than from the wounds themselves. But British pharmaceutical companies were already inundated with defense orders, so in 1941 Flory and Heatley went to the United States. Carrying mold in a bottle was too risky: someone could steal it and give it to the Germans. Heatley found a way out: he offered to soak the coat with fungal spores.

Purification of penicillin in a laboratory in England, 1943

The Americans were able to determine exactly what kind of mold started up at Fleming and went to the Oxfords.But for mass production, they did not use it, but a related one, which secretes six times more penicillin. She was found on a cantaloupe that an assistant brought from the market. The fungus was fed from sugar-rich corn waste. They began to grow mold in huge tanks with an electric stirrer, through which air was passed. If at the end of 1942 American penicillin was enough for less than 100 patients, then in 1943 already 21 billion doses were released, and in 1945 - 6, 8 trillion doses. A new era has begun.

The medical revolution is coming to naught

Penicillin and other antibiotics, which appeared in the first post-war decades, turned medicine upside down: most of the pathogenic bacteria were defeated. But something happened that Fleming had foreseen. Antibiotics are ancient natural weapons in the endless struggle of species for survival. Bacteria don't give up that easily. They multiply rapidly: for example, the cholera pathogen divides about once an hour. In just a day, Vibrio cholerae has as many generations of descendants as people have born since the time of Ivan III. This means that bacteria evolve just as quickly.

The widespread use of antibiotics - counting millions of tons over the entire time - only accelerates evolution: resistant bacteria produce offspring, and those that are affected by drugs disappear. A 2016 report to the UK government found that antibiotic-resistant microbes kill 700,000 people every year. If nothing is done, by 2050, 10 million people will die every year, and the total economic damage will reach an unimaginable $ 100 trillion.

New antibiotics could partially solve the problem, but they appear less and less. It is simply not profitable for pharmaceutical companies to bring them to the market. Unlike some antidepressants, they need to be taken very rarely, and the extremely cheap drugs of the past generations that can be produced without a license in developing countries compete with new drugs. The same report to the British government estimates that on average antibiotics only start to make a profit in the 23rd year, but soon after, their patent expires and anyone can make them.

At least half of antibiotics are used in agriculture

But even if new effective antibiotics do come on the market, there is no doubt that sooner or later the bacteria will adapt to them too. How quickly this happens depends on how the drugs are used. There are two problems here. First, at least half of antibiotics are used in agriculture: on huge livestock farms, where livestock, birds and fish live almost on each other's heads - and where the infection is spreading rapidly. Secondly, in many countries, antibiotics are sold without a prescription, so they are taken uncontrollably. But the fact is that the inhabitants of these countries sometimes either have no one to turn to, or nothing to. Leaving them without antibiotics is doomed to death.

Giving up cheap animal proteins and providing medical care to everyone in need is much more difficult than finding a new healing mold and bringing a drug based on it to the market. But until these two problems are resolved, the search for new antibiotics will only delay the time when a cut on a finger becomes a fatal risk.

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