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Clips of Time: From Bad Air to Invisible Bugs

Updated: Apr 19, 2021

For a long time, humans have had a basic understanding that something unseen caused disease. Though not always known by this name, the miasmic theory prevailed from the 4th century to the 19th century. The miasmic theory was the belief that “bad air” was the cause of illness. Bad air could have been from swamp gasses, the smell from rotten foods, or later from pollution.

It is easy to want to criticize the miasmic theory as silly or primitive, but it was a theory based on observation. The belief that disease was caused by something that could be detected by our senses is no less strange then germs that are invisible to the human eye. The miasmic theory was rooted in logic and that is probably why it prevailed for so long.

Things began to change in the 19th century during the midst of a cholera pandemic. Dr John Snow pioneered the field of epidemiology to prove that cholera was not caused by miasma, but by contaminated water. Snow was unconvinced that miasma was the cause of cholera and in 1854 he was given a chance to prove his theory. Snow investigated an outbreak of cholera in west London. By interviewing residents of the area, Snow was able to trace the source of the outbreak to a single water pump on Broad Street. Snow published his theory in 1855 but it was not received well by the medical community. His theory was not credited until after his death.

At almost the same time, another pair of men were working towards germ theory. Louis Pasteur and Joseph Lister should also be recognized for their work towards eliminating the theory of miasma. Snow’s work and Pasteur’s theory that fermentation was caused by microorganisms helped inform Lister’s theory. Lister was a surgeon who was disturbed by the number of patients who were killed by sepsis after surgery. After much study, Lister became convinced that sepsis was caused by microorganisms transported by the air. He began using carbolic acid to dress wounds to great success. Unfortunately, like Snow, his work was discredited initially by the medical community.

Doctors had a hard time taking germ theory seriously when it was first presented by men like Joseph Lister. Accepting germ theory meant that physicians had to accept that their patients often died by their own hands. By the time of the American Civil War, doctors were slowly coming to accept germ theory. Lister’s work and Florence Nightingale’s hand-washing campaign gained traction during the war. By the 20th century, germ theory had mostly been accepted in the medical community though still was much unknown about a variety of diseases.

Throughout the 20th century, there were plenty of different newspaper segments which were written in order to educate the public about matters of health and hygiene. An article in the Alamance Gleaner, published January 15th, 1925, entitled “Why Some Germs Are Invisible” helped the common person understand this scientific advancement. A portion of this article can be found below:

“An invisible germ cannot be studied. This means that until a germ is made visible, there is no way of knowing where it can be found in the body, how it affects the various organs, how it gets out of the body or in what form, what it lives on outside the body, whether it is carried by other animals or insects, how it gets back to the human body and how it can be controlled and the infection of healthy persons be avoided.

"One hundred years ago, smallpox and yellow fever were equally mysterious. No one knew the cause of either disease. No one knew whether they were carried by animals or insects, whether contact with the sick person would cause it.

Today, we know that only mosquitoes can carry yellow fever, so we disregard everything else in controlling this disease. We suspect everything about a smallpox patient. Just as our forefathers did 100 years ago.

"Someday, the germ of smallpox will be found and then it will be as easy to stamp out this disease as it is to control yellow fever.”

This article would have helped farming families, who often had little education and no access to libraries, learn more about germs and disease. It is an article that would have inspired hope in a family who would have dealt with diseases like smallpox firsthand. Smallpox has since been eradicated from the world due to hygienic changes and the smallpox vaccine.

In this day and age, it is more important than ever to remember the accomplishments of the scientists and physicians who came before us. Through the discovery of germs, the human race has defeated many of the diseases that once plagued the earth. With time, and proper hand washing, we too will defeat what ails us.

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