Germ theory of disease
The Germ theory of disease, developed in the 1860s and 1870s by Louis Pasteur, states that tiny "living beings" are the cause of infectious diseases. The theory was developed to explain puerperal fever, or Child bed fever. Beginning sometime in the nineteenth century, science began replacing the millennial old practice of midwifery, and physicians began delivering babies in hospitals. Puerperal fever was transmitted from patient to patient on the hands of the attending physician, and both women and the new born frequently died within days. Dr. Ignaz Semmelweis, using the controversial theory of microscopic organisms tinier than the eye could see was the first to insist that all practitioners must wash their hands before having contact with women in childbed, and Joseph Lister, who first introduced antisepsis into surgical practice.
He showed that the theory of spontaneous generation was false, by placing one piece of meat under a glass jar and another in an open dish. He observed flies landing on the exposed meat, but of course flies could not penetrate the glass jar. Flies did not come out of nothing, but from eggs deposited by flies which he could easily see landing on the exposed meat.
The theory that bacteria (and later, viruses) cause disease eventually became a corner of modern medicine, but first it faced an uphill battle. The idea that infection could be spread by invisible substances was opposed vigorously by doctors in Vienna when proposed by Ignaz Semmelweis. He reduced the incidence of mothers dying after childbirth from infection from 20% to near-zero, but other doctors resisted his efforts and got him fired.
Prior to germ theory, it was widely believed that disease was spread by noxious odors. As disease-spreading conditions - rotting meat, open sewage, and such things - was often highly odorous, the smell and disease were associated. Disease was also often attributed to demonic possession - although demonic possession must be possible as it it mentioned in Scripture, it is a rare occurrence, and almost all disease attributed to it was a result of other causes.
The Christian Scientist sect, founded by Mary Baker Eddy, believes that the Germ Theory of Disease is not true and that it is contradicted by Scripture. God created all life, and so all life should reflect His glory and inherent goodness - God could not have created pathogenic organisms, as these are inherently contrary to His nature.
- Prevailing Theories of Cholera School of Public health, UCLA
- Mark 5:1-13
- Lecture notes for a course at Ohio State University