During the pandemic, parents suddenly became obsessed about keeping kids away from all germs. Remember going out to dinner and feeling that even outdoors, even masked, it was still too risky if the kids touched each other?
I’ve been surprised to see that even after the pandemic ended, this behavior persisted. A child gets too close to another kid with a runny nose or a cough and a parent pulls him back. “Don’t touch.” “Don’t share.” “Don’t get sick.” One of my children’s friends canceled a playdate because he had been sick the week before.
Childhood is supposed to involve contact with the world itself. The immune system appears to benefit from ordinary contact with a world that has not been sanitized flat: soil, animals, other children, and early exposure to foods. The clearest example is peanuts: Early introduction lowers the risk of peanut allergy. The same pattern holds for pet exposure. Early-life contact with dogs and cats appears to reduce the risk of allergies, asthma, and food sensitivities.

