Alexander Fleming

Life and legacy

Alexander Fleming was born on a remote farm in Ayrshire, Scotland, in 1881, the seventh of eight children. After working as a shipping clerk in London, he used a small inheritance to study medicine at St Mary's Hospital Medical School in Paddington, qualifying in 1906. He joined the research department under Sir Almroth Wright, a pioneer of vaccine therapy, and spent his career at St Mary's.

During World War I, Fleming served as a captain in the Royal Army Medical Corps, working in battlefield hospitals in Boulogne, France. He witnessed countless soldiers dying not from their wounds but from infections that antiseptics could not reach - antiseptics often did more harm than good by destroying the body's own immune defenses while leaving deep-seated bacteria untouched. This experience convinced Fleming that what medicine needed was a substance that could kill bacteria without harming human tissue.

In 1922, Fleming discovered lysozyme, a natural antibacterial enzyme found in human tears, nasal mucus, and egg whites. Though lysozyme proved too weak to combat serious infections, the discovery demonstrated Fleming's keen observational skills. Then, on September 3, 1928, returning from a holiday, Fleming noticed that a petri dish of Staphylococcus bacteria had been contaminated by a mold - later identified as Penicillium notatum. Around the mold, the bacteria had been killed. Rather than discarding the contaminated plate, Fleming investigated. He found that the mold produced a substance - which he named "penicillin" - that was effective against a wide range of disease-causing bacteria.

Fleming published his findings in 1929, but he lacked the resources and chemical expertise to purify and mass-produce penicillin. It was not until 1940-1941 that Howard Florey and Ernst Boris Chain at Oxford University developed methods to produce penicillin in quantities sufficient for clinical use. By D-Day in June 1944, enough penicillin was being manufactured to treat all wounded Allied forces. Fleming, Florey, and Chain shared the Nobel Prize in Physiology or Medicine in 1945.

Fleming was knighted in 1944 and received honors from around the world. He remained modest about his discovery, frequently noting the role of chance and emphasizing the crucial contributions of Florey and Chain. He died of a heart attack in London on March 11, 1955. Penicillin and the antibiotics it inspired are estimated to have saved over 200 million lives, making Fleming's accidental observation one of the most consequential moments in the history of medicine.

Key accomplishments

• Discovered penicillin in 1928, launching the antibiotic revolution in medicine
• Discovered lysozyme, a natural antibacterial enzyme, in 1922
• Shared the Nobel Prize in Physiology or Medicine in 1945 with Florey and Chain
• Served in World War I battlefield hospitals, witnessing the inadequacy of existing antiseptics
• Knighted in 1944 for his contributions to medicine

Timeline

The dated lines from the record above, in order, with Alexander Fleming's age worked out from the birth year (1881).

1. 1881Born August 6, 1881, Lochfield, Ayrshire, Scotland
2. 1922Discovered lysozyme, a natural antibacterial enzyme, in 1922 (around age 41)
3. 1928Discovered penicillin in 1928, launching the antibiotic revolution in medicine (around age 47)
4. 1944Knighted in 1944 for his contributions to medicine (around age 63)
5. 1945Shared the Nobel Prize in Physiology or Medicine in 1945 with Florey and Chain (around age 64)
6. 1955Died March 11, 1955, London, England

Quotes

One sometimes finds what one is not looking for.

Nobel Banquet speech, December 10, 1945

When I woke up just after dawn on September 28, 1928, I certainly didn't plan to revolutionize all medicine by discovering the world's first antibiotic, or bacteria killer. But I suppose that was exactly what I did.

Widely attributed in biographical accounts

Related figures

Where Alexander Fleming sits in the atlas

• Era: The Modern Era (~1880-1965), one of 16 figures filed there
• Born 1881, the 115th of 125 figures in the full list by birth year.
• City: London
• Collection: Scientists Who Changed Everything

Contemporaries

30 other figures in the atlas were alive at some point during Alexander Fleming's lifetime (1881-1955). These are the longest overlaps.

• Albert Einstein (1879-1955): both alive for 74 years, 1881 to 1955
• Pablo Picasso (1881-1973): both alive for 74 years, 1881 to 1955
• Winston Churchill (1874-1965): both alive for 74 years, 1881 to 1955
• Coco Chanel (1883-1971): both alive for 72 years, 1883 to 1955
• Dwight D. Eisenhower (1890-1969): both alive for 65 years, 1890 to 1955
• Franklin D. Roosevelt (1882-1945): both alive for 63 years, 1882 to 1945
• Nikola Tesla (1856-1943): both alive for 62 years, 1881 to 1943
• Sigmund Freud (1856-1939): both alive for 58 years, 1881 to 1939

Others connected with the same city

Figures not already listed on this page, nearest in time first.

More from The Modern Era

Figures from the same era born closest in time to Alexander Fleming.

• Theodore Roosevelt (1858-1919), The Rough Rider President
• Rosa Parks (1913-2005), The Mother of the Civil Rights Movement
• Anne Frank (1929-1945), The Voice of the Holocaust
• Martin Luther King Jr. (1929-1968), The Dream of Justice