{"id":4891,"date":"2022-10-13T10:00:00","date_gmt":"2022-10-13T10:00:00","guid":{"rendered":"https:\/\/modernsciences.org\/staging\/4414\/?p=4891"},"modified":"2022-09-30T08:31:31","modified_gmt":"2022-09-30T08:31:31","slug":"louis-pasteurs-scientific-discoveries-in-the-19th-century-revolutionized-medicine-and-continue-to-save-the-lives-of-millions-today","status":"publish","type":"post","link":"https:\/\/modernsciences.org\/staging\/4414\/louis-pasteurs-scientific-discoveries-in-the-19th-century-revolutionized-medicine-and-continue-to-save-the-lives-of-millions-today\/","title":{"rendered":"Louis Pasteur\u2019s scientific discoveries in the 19th century revolutionized medicine and continue to save the lives of millions today"},"content":{"rendered":"\n
\n \n
\n Louis Pasteur was a pioneer in chemistry, microbiology, immunology and vaccinology.\n pictore\/DigitalVision Vectors via Getty Images<\/a><\/span>\n <\/figcaption>\n <\/figure>\n\nRodney E. Rohde<\/a>, Texas State University<\/a><\/em><\/span>\n\n

Some of the greatest scientific discoveries haven\u2019t resulted in Nobel Prizes.<\/p>\n\n

Louis Pasteur<\/a>, who lived from 1822 to 1895, is arguably the world\u2019s best-known microbiologist. He is widely credited for the germ theory of disease<\/a> and for inventing the process of pasteurization \u2013 which is named after him \u2013 to preserve foods. Remarkably, he also developed the rabies<\/a> and anthrax<\/a> vaccines and made major contributions to combating cholera<\/a>.<\/p>\n\n

But because he died in 1895, six years before the first Nobel Prize<\/a> was awarded, that prize isn\u2019t on his resume. Had he lived in the era of Nobel Prizes, he would undoubtedly have been deserving of one for his work. Nobel Prizes, which are awarded in various fields, including physiology and medicine<\/a>, are not given posthumously.<\/p>\n\n

During the current time of ongoing threats from emerging or reemerging infectious diseases, from COVID-19<\/a> and polio to monkeypox<\/a> and rabies<\/a>, it is awe-inspiring to look back on Pasteur\u2019s legacy. His efforts fundamentally changed how people view infectious diseases and how to fight them via vaccines. <\/p>\n\n

I\u2019ve worked in public health and medical laboratories<\/a> specializing in viruses and other microbes, while training future medical laboratory scientists<\/a>. My career started in virology with a front-row seat to rabies detection and surveillance<\/a> and zoonotic agents, and it rests in large part on Pasteur\u2019s pioneering work in microbiology, immunology and vaccinology. <\/p>\n\n

\n \"A<\/a>\n
\n An illustration of Louis Pasteur, right, supervising the administration of the rabies vaccine at the Pasteur Institute in Paris in 1886.<\/span>\n Library of Congress\/Interim Archives via Getty Images<\/a><\/span>\n <\/figcaption>\n <\/figure>\n\n

First, a chemist<\/h2>\n\n

In my assessment, Pasteur\u2019s strongest contributions to science are his remarkable achievements in the field of medical microbiology and immunology. However, his story begins with chemistry. <\/p>\n\n

Pasteur studied under the French chemist Jean-Baptiste-Andr\u00e9 Dumas<\/a>. During that time, Pasteur became interested in the origins of life and worked in the field of polarized light and crystallography<\/a>. <\/p>\n\n

In 1848, just months after receiving his doctorate degree, Pasteur was studying the properties of crystals formed in the process of wine-making when he discovered that crystals occur in mirror-image forms<\/a>, a property known as chirality. This discovery became the foundation of a subdiscipline of chemistry known as stereochemistry<\/a>, which is the study of the spatial arrangement of atoms within molecules. This chirality, or handedness, of molecules was a \u201crevolutionary hypothesis<\/a>\u201d at the time. <\/p>\n\n

These findings led Pasteur to suspect what would later be proved through molecular biology: All life processes ultimately stem from the precise arrangement of atoms within biological molecules.<\/p>\n\n

Wine and beer \u2013 from fermentation to germ theory<\/h2>\n\n

Beer and wine were critical to the economy of France<\/a> and Italy in the 1800s. It was not uncommon during Pasteur\u2019s life for products to spoil and become bitter or dangerous to drink. At the time, the scientific notion of \u201cspontaneous generation\u201d held that life can arise from nonliving matter, which was believed to be the culprit behind wine spoiling. <\/p>\n\n

While many scientists tried to disprove the theory of spontaneous generation, in 1745, English biologist John Turberville Needham<\/a> believed he had created the perfect experiment favoring spontaneous generation. Most scientists believed that heat killed life, so Needham created an experiment to show that microorganisms could grow on food, even after boiling. After boiling chicken broth, he placed it in a flask, heated it, then sealed it and waited, not realizing that air could make its way back into the flask prior to sealing. After some time, microorganisms grew, and Needham claimed victory. <\/p>\n\n

However, his experiment had two major flaws<\/a>. For one, the boiling time was not sufficient to kill all microbes. And importantly, his flasks allowed air to flow back in, which enabled microbial contamination.<\/p>\n\n

To settle the scientific battle, the French Academy of Sciences sponsored a contest for the best experiment to prove or disprove spontaneous generation<\/a>. Pasteur\u2019s response to the contest was a series of experiments, including a prize-winning 1861 essay<\/a>. <\/p>\n\n

Pasteur deemed one of these experiments as \u201cunassailable and decisive\u201d because, unlike Needham, after he sterilized his cultures, he kept them free from contamination. By using his now famous swan-necked flasks, which had a long S-shaped neck, he allowed air to flow in while at the same time preventing falling particles from reaching the broth during heating. As a result, the flask remained free of growth for an extended period. This showed that if air was not allowed directly into his boiled infusions, then no \u201cliving microorganisms would appear, even after months of observation.\u201d However, importantly, if dust was introduced, living microbes appeared.<\/p>\n\n

Through that process, Pasteur not only refuted the theory of spontaneous generation, but he also demonstrated that microorganisms were everywhere. When he showed that food and wine spoiled because of contamination from invisible bacteria rather than from spontaneous generation, the modern germ theory of disease was born<\/a>.<\/p>\n\n

\n