In 36 BCE, Roman statesman Marcus Varro wrote about germs, describing “minute creatures which cannot be seen by the eyes, which…enter the body through the mouth and nose and there cause serious diseases.” The germ theory of disease would not be accepted widely for another 1,900 years.

The germ theory of disease is the currently accepted scientific theory of disease. It states that many diseases are caused by microorganisms. “Germ” may refer to not just a bacterium but to any type of microorganism or even non-living pathogen that can cause disease, such as protists, fungi, viruses, prions, or viroids.[1] Microorganisms that cause …

In 36 BCE, Roman statesman Marcus Varro wrote about germs, describing “minute creatures which cannot be seen by the eyes, which…enter the body through the mouth and nose and there cause serious diseases.” The germ theory of disease would not be accepted widely for another 1,900 years. Read More »