The need for antibiotics during World War II spurred the rapid development of methods for the large-scale production of penicillin. Pharmaceutical companies in the United States, with support from the US government, developed fermentation techniques that allowed for mass production. Penicillin became a crucial weapon in the fight against bacterial infections in wounded soldiers.

As penicillin gained widespread use and saved countless lives, Fleming's role as the discoverer of penicillin became increasingly recognized. He was celebrated as a scientific hero, and his contributions to medicine were widely acknowledged.

Alexander Fleming was knighted by King George VI for his scientific achievements. He became Sir Alexander Fleming.

Fleming, Florey, and Chain were jointly awarded the Nobel Prize in Physiology or Medicine for the discovery of penicillin and its curative effect in various infectious diseases. This prestigious award cemented their place in scientific history.