Topic – Penicillin Saves the World

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Penicillin Saves the World

Alexander Fleming was a brilliant scientist—but he was also a messy one. So when he left his lab for a holiday in August 1928, he did not clean up the samples of bacteria he was growing. Fleming did not discover the results of his untidiness until he returned to work on September 3. What he saw changed the world.

An Incredible Discovery

When Fleming entered his lab, he realized he had left one of his bacteria samples open. Mould had dropped onto the sample and contaminated it. That meant Fleming would have to begin all over again. He picked up the sample to throw it away. But then he stopped and took a second look.

To his amazement, Fleming saw that where the mould had landed on the sample, it had killed the bacteria around it. The scientist was curious about how it did this. Fleming knew that more than 500 years ago, some doctors and healers had applied mouldy bread to wounds to help them heal. Sometimes it helped, but the healers did not know why.

Fleming was determined to find out more about his fascinating mould. He grew a sample of it and discovered that it gave off a bacteria-killing substance. He called the liquid “mould juice” at first. Then, after a few months, he named it penicillin after the Penicillin mould that created it.

Penicillin at Work

Penicillin was one of the first bacteria killers, or antibiotics, that scientists ever discovered and it changed the world of medicine. During World War I (1914–1918), Fleming had worked in hospitals on the battlefields in France. He had seen soldiers die of wounds that had become infected. Fleming was well aware of how helpful a drug that killed bacteria could be and how many lives it could save.

By the 1940s, scientists figured out how to mass-produce penicillin, which meant it was soon available around the world to many patients. Doctors used the drug to treat diseases that had affected people for many thousands of years. Illnesses such as gangrene (the death of tissue caused by poor circulation) and tuberculosis (a disease of the lungs) could finally be effectively battled.

The success of penicillin encouraged doctors to experiment and find similar drugs and more types of antibiotics that could be used to treat other infections. Today, drug companies have figured out how to make synthetic penicillin, which makes the drug even more available to a wider group of patients.

It is estimated that penicillin and other antibiotics have saved the lives of more than 200 million people over the years. It is hard to believe it all started with a messy lab and an observant scientist.

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