Weird Wednesdays: A blast from the Pasteur


Louis Pasteur, Spontaneous Generation, and Germ Theory. Image by Wikimedia Commons.

I’ve heard speculation that if Louis Pasteur were alive today, he would go around punching anti-vaxxers.

I disagree with this. Pasteur, genius as he was, wouldn’t resort to violence against the ignorant. He’d probably educate the masses. Failing that, he’d probably invent a vaccine against ‘em. Hey, if it clears my Facebook wall of regurgitated Jenny McCarthy rhetoric, I say sign me up!

Louis “The Father of Microbiology” Pasteur is a man we can give many thanks to. If you’ve ever been to a dog park, eaten beef or drunk milk, then it’s because of him you haven’t died horribly from multiple diseases. I’d tell you to send a card, but he’s been dead for over a century.

Pasteur was born in 1822 in the French commune of Dole. The middle child of poor leather tanners, he spent most of his school days drawing and painting instead of focusing on his GPA. He failed his first exam in general science in college and lagged in chemistry before attending the elite teaching school École Normale Supérieure and getting his Master’s.

He taught physics there for a while, and married Marie Laurent, the daughter of the university rector (which is a church-dude). While there, Louis discovered that certain crystalline structures are three-dimensional on a molecular scale, and that they could rotate light in certain directions– a discovery that would later be crucial for the development of modern microscopes and telescopes.

In 1848, he began teaching chemistry at the University of Strasbourg, where he began to study the finer points of fermentation.

Now, you probably know that fermentation is caused by microbes (usually yeasts and bacteria) breaking down the organic matter they live in and producing byproducts, which can be anything from gas to alcohol. Fermentation can be good or bad; good when you’re making beer, bad when you’re trying to preserve a jug of milk.

Back in the day, however, fermentation was thought to be a spontaneous process. By the time Louis really got into it in 1856, fermentation was said to be caused by standard decomposition (which itself was thought to be caused by a simple chemical reaction, no biological agents involved.)

Louis was having none of it. He experimented with wines (hey, it’s France!) and found that the addition of the same yeasts used in beer-making to pre-fermented wine resulted in better, more consistent products. Wine exposed to air, however, was found to become ‘sour,’ infested with unwanted microbes that produce lactic acid instead of alcohol.

After experimenting with aerobic (air-open) and anaerobic (no-air) fermentation, Patsy took it a step further and decided to see what caused food spoilage and sickness in the first place.

At the time, the silkworm industry was a big one in France. Post-revolution Regency styles were in, and silk was needed for skirts, scarves, gloves and fans alike. A pervasive malady, however, was tearing through France’s silkworm population and turning the larvae to goop. Pasteur was commissioned by the state to solve the mystery.

Though he knew nothing about silkworms, Louis was nothing if not methodical. Through microscopic analysis, as well as behavioral observation, he was able to determine not only that two different types of microbes were causing the disease, but also that extrinsic factors such as temperature, humidity and the caterpillars’ diet had a role in how quickly they succumbed.

In time, Pasteur found that subjecting a substance to high temperatures–between 60 to 100℃– destroyed the residual bacteria within them and kept them from spoiling quickly. This process, which is applied to milk, beer, apple cider and other beverages, is known as today as pasteurization.

As if he didn’t save enough lives with this technique, as well as his tireless crusade alongside Joseph Lister campaigning for cleaner hospitals and surgery rooms, Louis went on to discover (and invent the vaccines for) not one or two, but THREE deadly diseases in his lifetime.

And I had trouble getting out of bed this morning.

The first on Pasteur’s kill list was chicken cholera, which is caused by a bacteria that more or less eats the bird inside out. Pasteur had been studying the microbes and was sent a culture by a friend of his. However, when Louis inoculated three healthy chickens with the gifted microbes, they didn’t get sick– even when exposed to fresh virus.

The bacteria, Pasteur theorized, was weakened by the oxygen in the air, providing the perfect punching bag for the chickens’ immune system to practice on–the same principle that had helped Edward Jenner develop the world’s first vaccine for smallpox in 1776.

Anthrax was next on the list. This bacteria is particularly dastardly because it’s not only incurable and fatal to both livestock and humans, but because it can withstand most environmental conditions due to its ability to form spores, leaving it in fields for years at a time. When Pasteur was told that a ‘cursed’ field was a source of an anthrax outbreak in sheep, he did some digging. Literally.

The farmer, it turned out, had used the field to bury sheep who had died of (guess what!) anthrax. Earthworms had brought the spores to the surface, infecting the flock above. After telling the farmer to move the field, and after creating a harmless strain of anthrax by heating it, Pasteur saved the day once again with a vaccine and a bit of sense.

His final claim to fame was the greatest.

In the 1800s, the rabies virus was a scourge upon the populus. A bite from a mad dog was all but a signed death warrant; the disease was 100 percent fatal, and there was nothing to be done but to offer the victim a pistol in hopes of sparing them an agonizing, hydrophobic, paralyzing death.

Even today, there’s no treatment for a symptomatic patient if they haven’t been vaccinated beforehand (with a few exceptions, but that’s for another column.)

Pasteur sought to change this. His ‘weakened microbe’ theory could be applied to rabies, he figured, but obtaining samples would prove to be difficult. The virus isn’t found in the environment; only in infected individuals. To get the initial samples, Pasteur and his assistants spent an inordinate amount of time attempting to get saliva samples from restrained rabid dogs. (A loaded firearm was kept nearby in case anyone was nicked in the process.)

The virus, which resides in the nervous tissue, was weakened by drying out the spinal cords of inoculated rabbits Pasteur raised. The first trial was conducted in 1885 on a 9-year-old boy, Joseph Meister, who had been savaged by a rabid dog, and thus condemned to die.

(Spoiler alert: He didn’t. It worked.)

Basking in his successes, Pasteur was hailed a national hero. He continued to tour around Europe, giving lectures and promoting good hygiene, until a stroke left him bedridden in 1894. He died a year later, at the ripe old age of 73.

I could go on for ages about Pasteur, but I won’t. Instead, I implore you to be inspired by his fearlessness, his innovation and his dedication to science and public health. He’s paved the way for doctors and researchers alike, and set the groundwork for life-saving vaccines in the coming decades.

You don’t have to send a card. Just be sure you’re up-to-date on your shots. Stay immune, dear readers… and stay weird.

Marlese Lessing is the news editor for The Daily Campus. She can be reached via email at She tweets @marlese_lessing.

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