Science: Magnificent Progress and Missed Opportunities
The history of science is largely a history of growth and discovery. Since the scientific revolution near the end of the Renaissance, scientific thought has produced an unending string of achievements, from milk pasteurization to moon landings. It has also, however, had its share of missteps and missed opportunities. Today, let’s explore a story of one of those missed opportunities—Antonie van Leeuwenhoek and his missed contribution to germ theory.
Microbes in Your Mouth
First, never has any scientist’s name been misspelled and mispronounced in so many different ways as Leeuwenhoek’s. I have seen Leuwenhoek, Leeuwenhoek, Leuwenhoek, Anton, Antony… It’s not just a modern problem. In fact, there were some 19 different published spellings of van Leeuwenhoek’s name in the Annals of the Royal Society of London while he was still alive.
Leeuwenhoek did many things throughout his long life. He was probably an associate of the painter Dutch Johannes Vermeer and appears as such in the 2003 movie Girl with the Pearl Earring. In his 40s he began making small, single lens microscopes. His microscopes were significantly better than any others available at the time and there is still some mystery concerning how he made them, as he was not willing to reveal his secrets during his lifetime. Leeuwenhoek was the first to see microorganisms, including bacteria and protozoans, as well as other microscopic structures and critters that other microscopes would not see for some 200 years. He is commonly known as the Father of Microbiology. Leeuwenhoek took scrapings from his own teeth and those of others and examined them with his microscope. He was surprised to see small creatures that he called animalcules (little animals) swimming and moving about through his microscope. “I then most always saw, with great wonder, that in said matter there were many very little living animalcules, very prettily a-moving.” This was likely the first description of bacteria. Many of his observations were published by the recently formed Royal Society of London.
Leeuwenhoek repeated his experiment often. He was mildly alarmed when, one evening, he found no movement of the animalcules in his mouth. He realized that he had just drunk very hot coffee, so perhaps the heat killed the small creatures. He repeated this experiment and found that it was reproducible. In fact, he found that by boiling a sample of microbes from any source—garden soil or pond water for example—the animalcules were killed! All this, he reported to the Royal Society. The scientific community had all the evidence they needed to know that heat kills microbes. And yet, it would be over 150 years before anyone even dreamed of sterilizing surgical instruments in boiling water.
Germ Theory of Disease
There is no way to calculate the cost in human life of not applying Leeuwenhoek’s published observations involving the heat treatment of microorganisms to medicine and surgery. How many mothers would die of sepsis because midwifes and physicians never even considered boiling water brought to the delivery bed? How many vicious infections and slow painful deaths did field surgeons using the same blades and bone saws on one patient after another cause? Why, if it was know for more than a century and a half that heat treatment killed bacteria and other animalcules didn’t even the brightest doctors simply boil their instruments or even worry about washing their hands between patients? They simply had no idea that germs caused disease!
In the latter half of the 1800s, a number of scientists, perhaps most famously Louis Pasteur, proposed that germs could cause deadly disease. The germ theory was born. Even so, not all surgeons bought into the concept.
If you go to the Philadelphia Museum of Art you can see a famous painting by Thomas Eakins titled The Gross Clinic, a title perhaps more apt than Eakins knew. The painting depicts Dr. Samuel D. Gross operating on a young man’s leg in the surgical amphitheater at Jefferson Medical College. Dr. Gross and his colleagues are in street clothes, probing the wound with bare hands while a woman in black, perhaps the wife or mother of the patient, cringes nearby. Eakins did this painting in 1875; a decade after Pastures work was published. Dr. Gross did not believe in the power of germs to cause disease and infection.
Fortunately, other doctors, including the British surgeon Joseph Lister, saw Pasture’s work very differently. Noting that phenol or carbonic acid killed microbes, Lister devised in 1865 a vaporizer that assistants would use to spray the operative field during surgery with the “anti-septic”. He also used carbonic acid-soaked gauze and bandages to dress surgical wounds. Prior to introducing his antiseptic technique, the death rate of Lister’s surgical patients was nearly 46%. After introducing the new antiseptic treatment, the death rate fell to 15%. Interestingly, notice in the picture shown here that the doctors were still wearing their street clothes in surgery! This is because Lister’s technique was only antiseptic. The aseptic technique, in which sterile gowns, gloves, masks and instruments are used, came somewhat later.
The Story Comes Full Circle
As a side note, the product Listerine was named after Lister around 1879. Although originally developed as a surgical antiseptic, it was soon used as a floor cleaner and disinfectant. It was also used to treat gonorrhea before being marketed, most successfully, as a mouthwash. There is no phenol or carbonic acid in Listerine.
So the story comes full circle in two hundred years. In the late 1600s, Leeuwenhoek discovered microbes in his mouth. In the late 1800s, Listerine was marketed to kill germs in the mouth and prevent bad breath. Perhaps if Leeuwenhoek had access to Listerine, his animalcules would have had to await discovery for quite some time!
The history of science is full of magnificent progress. There are also ample examples of unfortunate missed opportunities. Sometimes only in retrospect can we tell the difference. And that’s just one reason that science is so utterly fascinating and alive.