On this day: Alexander Fleming, discoverer of penicillin, dies

The antibiotic penicillin is estimated to have saved 200 million lives worldwide since it was discovered in 1928.

Scottish researcher Alexander Fleming discovered the antibiotic in 1928 while conducting unrelated research into the influenza virus.

His discovery was to win him the Nobel Prize.

Fleming noticed that mould had grown in dishes used to grow cultures of staphylococci bacteria - and that around the mould, there were clear circles.

He found that a mould culture prevented growth of staphylococci, even when diluted 800 times.

Fleming named the substance penicillin. after the mould penicillium - commonly found on rotting food, and in soil.


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Fleming was born in 1881 in Ayrshire, and served in the Army Medical Corps in World War One after qualifying as a doctor. Fleming died on March 11, 1955.

He was awarded the Nobel in 1945 - after two other scientists, Australian Howard Florey and Ernst Chain had done further work that allowed penicillin to be produced as a drug.

The drug he had discovered became an effective antibiotic during the war.

As techniques improved the drug was 20 times more concentrated by 1945 than it had been in 1939 - and significantly more effective.

It was especially good at dealing with gangrene.

By treating once deadly infections, penicillin is today estimated to have saved 200million lives – almost three times the number who died in the war.