In the late 19th century, many thought bacteria were mere byproducts of illness until German physician Robert Koch proved the germ theory of disease. By isolating a microbe, infecting an animal, and re-isolating it, he not only established the link between microbes and disease but also silenced critics and revolutionized medicine. Origins: The Journey of Humankind is streaming on Disney . | National Geographic History

Germ theory denialists like RFK Jr, Joe Rogan, Bill Maher, and other conspiracy theorists are rejecting 200 years of data. It just goes to show you that there is no amount of evidence that will change these people’s minds. Germ theory denialism is the false belief that pathogenic microorganisms (viruses, bacteria, parasites) don’t cause disease, but it’s your “internal environment” and your physiology that causes someone to get sick. It’s not the measles virus, it’s your nutrient imbalance. Soun