Fleming Dies: Penicillin's Discoverer Leaves a Legacy

A forgotten petri dish changed the course of medicine. Alexander Fleming returned from a two-week vacation to his laboratory at St. Mary's Hospital in London in September 1928 and noticed that a mold colony had contaminated one of his staphylococcus cultures. Rather than discarding the plate, Fleming observed that bacteria near the mold had been destroyed. He identified the mold as Penicillium notatum and named its antibacterial secretion penicillin. Fleming published his findings in 1929, but the scientific community largely ignored the discovery. He lacked the resources and chemistry expertise to purify penicillin into a usable drug, and the paper attracted minimal attention for over a decade. Fleming himself moved on to other research, convinced the substance degraded too quickly to serve as a practical treatment. Howard Florey and Ernst Boris Chain at Oxford University revived the work in 1940, successfully purifying penicillin and demonstrating its extraordinary effectiveness against bacterial infections. The first human trial saved a policeman dying from septicemia, though supplies ran out before the treatment could be completed. By 1944, mass production in the United States generated enough penicillin to treat every Allied soldier wounded on D-Day. Fleming, Florey, and Chain shared the 1945 Nobel Prize in Physiology or Medicine. Fleming became a global celebrity, knighted in 1944, and showered with honorary degrees from universities worldwide. He spent his later years warning about antibiotic resistance, cautioning that bacteria would evolve to defeat penicillin if the drug was misused. Fleming died of a heart attack at his home in London on March 11, 1955, at age seventy-three. The accidental discovery he almost threw away has since saved an estimated 200 million lives.