Alexander Flemming in his Laboratory at St. Mary's Hospital, London. |
On September 28, 1924 Dr. Alexander Fleming, a Scottish physician and researcher,
stumbled on one of the most
significant accidental discoveries
in scientific history—and was smart enough to understand what it meant.
Fleming was born to middling farmers on August 6, 1881 at Lochfield, a farm near Darvel
in Ayrshire, Scotland. Although he got excellent marks in school,
and small scholarships allowed him
to enroll at the Royal Polytechnic Institution for studies in biology, he was unable to continue his education and
worked as a shipping clerk for some
years before a small inheritance
allowed him to enroll in medical school at St Mary's Hospital in Paddington, London. He graduated
with honors in 1906 qualified as a surgeon.
Instead of going into practice as a surgeon, however, Fleming
was encouraged to join the research department at St Mary's, as
assistant bacteriologist to Sir Almroth Wright, a pioneer in vaccine therapy and immunology. He earned an M.B. degree and then a B.Sc. with Gold Medal in 1908. He stayed at St. Mary’s as a lecturer in biology until the War broke out in 1914.
As a captain in the Royal Army Medical Corps, Fleming served with distinction and was cited for bravery in advanced
field hospitals on the Western
Front. At War’s end he returned to
St. Mary’s determined to
find antibacterial agents.Flemming's contaminated culture--a blob of mold, left, killed the bacteria near it. |
after a long holiday with his family in
Scotland. He had left a pile of petri dishes containing bacteria samples on a laboratory bench having forgotten to refrigerate them. He was
going to discard the ruined samples when he noticed the
bacteria in one dish were being killed by an invading grey/green fungus.
Fleming, who had been actively looking for anti-bacterial agents since
his World War I time service in France where he saw many men lose limbs or their lives to septicemia from infected wounds, understood that something in that fungus
could kill bacteria.
Fleming first called the
substance that killed the bacteria simply mold
juice. After some difficulty, he identified the mold as a member of the Penicillium genus and named the substance penicillin when he published
his finding in the British Journal of Experimental Pathology in 1929.
He found penicillin very difficult to produce and despaired that
it could be produced in sufficient
quantities to become important in treating
infections. He did recognize that if
penicillin were used in insufficient
concentrations or over too short a
period of time, that the bacteria evolved
to become resistant to the
serum. He also identified many bacterial
organisms against which it was effective, including those that caused scarlet fever, pneumonia, meningitis, diphtheria, and gonorrhea but not infections like typhoid fever. Fleming
therefore cautioned that if used, it must only
be applied to those illnesses for which it was proven effective and in sufficient
strength of and then only in sufficiently
high doses over an extended period
of time in order to prevent the
spread of drug-resistant bacterial strains.
As Fleming continued his
research into the 1930’s he became further discouraged. He was applying penicillin primarily as a topical application to open wounds. He began to fear that the serum would not
live long enough in the body to become effective against deep infections. Later, he
began to experience better results, but without a method of producing the
antibiotic in mass quantity, he abandoned
his research and turned to trying to find other agents.
Fleming (center) receiving the Nobel prize from King Gustaf V of Sweden in 1945 as Ernst Chain and Howard Florey wait their turn. |
In 1939 German born Ernst Boris Chain and Howard
Florey at Oxford University took
up where Fleming had left off. They
discovered penicillin’s chemical
composition and accurately predicted
the physical structure of its molecule.
With a new war, both the
British and U.S. governments poured
money into research which led to mass
production techniques. By the time
of the D-Day invasion enough
penicillin was available to treat all of the Allied injured. By the end
of the war it was available worldwide.
In honor of their work
Fleming, Chain, and Florey shared the 1945 Nobel
Prize in Medicine.
Penicillin slashed death from infected wounds and battled venereal disease in World War II. |
More research has
developed other penicillin-like drugs. By mid-century the infectious diseases that
had been some of humanities most
persistent killers, were controllable
Fleming died, full of
honors, on March 11, 1955 in London at the age of 73. He did not live to see his often expressed
dire warnings about the emergence of drug resistant bacteria come fully to
reality. Years of routine over-prescription of penicillin and related antibiotics have led to the development of resistant superbugs which could possibly threaten
new, widespread epidemics.
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