Your great-grandparents faced infectious diseases that hardly threaten you today: tuberculosis, polio, cholera, malaria, yellow fever, measles, mumps, rubella, smallpox, typhoid, typhus, tapeworm, hookworm…. But there's also a long list of modern illnesses that your great-grandparents barely knew: asthma, eczema, hay fever, food allergies, Crohn's disease, diabetes, multiple sclerosis, rheumatoid arthritis. The coincidence of the rise in these "inflammation" diseases, characterized by an overactive immune system, with the decline of infection is almost certainly not a coincidence.

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