Skip main navigation

A warning from Fleming

An excerpt from Alexander Fleming's 1945 Nobel Prize acceptance speech for his, Howard Florey, Ernst Chain's discovery of Penicillin.
Photo of a penicillin fermentation flask
© Wellcome Genome Campus Advanced Courses and Scientific Conferences

Alexander Fleming, Howard Florey and Ernst Chain were awarded the Nobel prize in 1945 for the discovery of Penicillin, the world’s first broad-spectrum antibiotic. Very early in the discovery, they established the ease with which bacteria could develop resistance to Penicillin. In Fleming’s Nobel acceptance speech he ended with a warning for future generations:

“…But I would like to sound one note of warning. Penicillin is to all intents and purposes non-poisonous so there is no need to worry about giving an overdose and poisoning the patient. There may be a danger, though, in underdosage. It is not difficult to make microbes resistant to penicillin in the laboratory by exposing them to concentrations not sufficient to kill them, and the same thing has occasionally happened in the body. The time may come when penicillin can be bought by anyone in the shops. Then there is the danger that the ignorant man may easily underdose himself and by exposing his microbes to non-lethal quantities of the drug make them resistant. Here is a hypothetical illustration. Mr. X. has a sore throat. He buys some penicillin and gives himself, not enough to kill the streptococci but enough to educate them to resist penicillin. He then infects his wife. Mrs. X gets pneumonia and is treated with penicillin. As the streptococci are now resistant to penicillin the treatment fails. Mrs. X dies. Who is primarily responsible for Mrs. X’s death? Why Mr. X whose negligent use of penicillin changed the nature of the microbe. Moral: If you use penicillin, use enough…”

To read Sir Alexander Fleming’s full Nobel lecture: Penicillin, see the link below: https://www.nobelprize.org/uploads/2018/06/fleming-lecture.pdf © Nobelprize.org. Nobel Media AB 2014. Web. 26 Oct 2018

© Wellcome Genome Campus Advanced Courses and Scientific Conferences
This article is from the free online

Bacterial Genomes: Disease Outbreaks and Antimicrobial Resistance

Created by
FutureLearn - Learning For Life

Reach your personal and professional goals

Unlock access to hundreds of expert online courses and degrees from top universities and educators to gain accredited qualifications and professional CV-building certificates.

Join over 18 million learners to launch, switch or build upon your career, all at your own pace, across a wide range of topic areas.

Start Learning now