It’s one of the most famous stories in medical science: Scottish bacteriologist Alexander Fleming comes into his lab in London one day in 1928, and finds that bacteria on a test dish seem to have been wiped out by some mould that had landed in the dish. Fleming discovers the mould is secreting a compound he calls penicillin – it’s the world’s first antibiotic. Antibiotics have since saved countless people from deadly bacterial infections.
Yet Fleming himself was unconvinced penicillin could be turned into an effective treatment and lost interest in his discovery. Credit for turning a chance finding into one of the greatest medical breakthroughs ever should go to the Australian pathologist Howard Florey and the German-born biochemist Ernst Chain. During the late 1930s, they purified and stabilised penicillin, and in 1941 became the first to treat a patient. Despite a brief improvement, the patient died, as there wasn’t enough of the wonder drug. This led Florey to cajole the giant US pharmaceutical companies into setting up mass-production facilities. By the D-Day landings of 1944 there was enough penicillin to treat thousands of injured troops who would otherwise have died. The following year, Fleming won the Nobel – along with Florey and Chain.
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