FWIW, this is overstated to the point of inaccuracy. Bubonic plague is caused by Yersinia pestis only, regardless of exposure level. Reduced exposure to commo

FWIW, this is overstated to the point of inaccuracy. Bubonic plague is caused by Yersinia pestis only, regardless of exposure level. Reduced exposure to common beneficial bacteria in young children might cause a mild increase in susceptibility to colds, allergies, asthma, eczema. Your examples have nothing to do with moderation.