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TERRY DOES SCIENCE!
PENICILLIN - The First Wonder drug
In the late 1920's a Scottish scientist Alexander Fleming was working in St. Mary's Hospital in London. His aim was to find an alternative to antiseptics.
At the time many people died from infection. Fleming himself had served in the First World War and he had seen first hand the huge number of people who had died from bacterial infection. Infection was in fact the main cause of death in the War. While antiseptics were used, their success rate was disappointing. In fact they often worked against the body's natural healing process.
As a research biologist, Fleming grew and experimented with various bacterial colonies that he grew on agar plates, and he examined the results of these plates. He wasn't a particularly tidy worker and his desk was regularly cluttered with lots of different culture plates.
Back in those days, they worked with glass plates and these were reusable. That meant that they needed to be sterilised and cleaned out. Fleming often left his plates for weeks on end before cleaning up.
By some stroke of luck, after coming back from holidays in September 1928, Fleming rechecked some of these old bacterial plates. He had a habit of doing this, and on one plate he noticed a fungal contamination. This wasn't unusual. In fact, it would be quite common. A spore would have blown in onto the plate that he was working with and it had started to grow, along with the bacterial colonies that he was working with.
But Fleming noticed something unusual. Although both bacterial and fungal growth were present on the plate, he could see that there was a definite inhibition of bacterial growth close to where the fungus was growing and he wondered, had the fungus released some substance into the surrounding agar and was this substance in some way preventing the bacteria from growing or killing them off.
The mould or fungus in question was a blue mould and it was identified as Penicillium notatum. Fleming concluded that a chemical was released from the fungus and he called it penicillin.
The following year, Fleming published a paper on his work with penicillin, stating that it could kill pathogenic microbes, and that it could be given to small animals without any side effects.
But this was as far as Fleming went. For some reason or other, he moved on to other projects.
Penicillin research took a back seat for another 10 years. By then, the Second World War had started and keeping in mind the number of soldiers that died from infection in the previous War, there was a renewed effort to try to prevent this happening again.
Two scientists, Howard Florey and Ernst Chain, were working in Oxford and they managed to isolate penicillin. Unfortunately, they could only extract tiny amounts, and it was far from pure. What they isolated was a yellow substance. In fact pure penicillin is white. We now know that, at best, what they extracted was only about 4% pure.
However, they decided to do some trials. They first tried it out on mice. In May 1945 they infected 8 mice with a deadly strain of bacteria. They gave 4 of these mice penicillin. Two days later, the four untreated mice were dead but those that were treated were alive and well. The penicillin had worked.
It was now time to try it out on humans but because a human is about 3,000 times the size of a mouse, they needed a lot more penicillin. This was a major problem, but they managed to produce enough to start a trial.
A young policeman was chosen. He was very ill and had already lost an eye to infection and was well on his way to death. Because they had so little penicillin, they collected his urine and as much penicillin as possible was extracted from it to be used again. Even still, they ran out of the drug after 4 days. The patient had shown huge improvement, but unfortunately he relapsed and sadly he died.
But again, it showed that penicillin DID work.
They now decided it was now time to turn to the U.S. for help to mass produce this wonder drug. Florey brought his mould over to the States and when the U.S. entered the War less than 6 months later, the pharmaceutical companies had pooled their efforts to make it.
By 1943 British companies were also making vast quantities so that when D-Day arrived there was enough penicillin to treat all Allied casualties. And the wonder drug, penicillin, was one of the real hero's of the Second World War, saving the lives of thousands of men.
It's even been suggested that Adolf Hitler was treated with penicillin, following an assassination attack. At the time, only the Allies had access to it, but it's thought that it was obtained by the Germans from Allied airmen who carried penicillin and were captured.
In 1945, Fleming, Florey and Chain were awarded the Nobel Prize for the discovery and development of penicillin.
Today, there are lots of different antibiotics apart from penicillin. Antibiotics are among the most commonly prescribed drugs by doctors. They have been hugely successful in combating bacterial and fungal infections and they have definitely improved our standard of living.
However, we have become somewhat blasé about our use of antibiotics. We don't treat them with the respect we should. We regularly don't finish the full course of antibiotics or we take them for infections for which they have no effect, infections like colds or flu.
This has led to strains of microbes becoming immune to antibiotics, which means that stronger, more powerful antibiotics are needed.
Even so, certain strains of microbes, the so called superbugs have evolved. These, like MRSA and C.diff. are extremely difficult to treat.?
We should only take antibiotics when we absolutely need to and we should always complete the full course of tablets.
It's difficult to know where we'd be today without the development of antibiotics. What if Fleming hadn't accidentally come across that contaminated plate back in 1928. As Fleming himself said: It is the lone worker who makes the first advance in a subject; the details may be worked out by a team, but the prime idea is due to enterprise, thought, and perception of an individual.
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