To the Editor.—The authors thank Dr. Tubbs for his thoughtful suggestions, and are grateful to the Journal for the opportunity to reply.
Our study has been motived by a biologist's inquisitiveness as to the natural ecological relationship between human host and a specific pathogen, and by a philosopher's desire to discover if there might be an inherent "goodness" in this pattern of relationships. It seems as if the pattern we have described must be the way that normal children do grow up in most of the world today, and have grown up during all human—and mammalian—history, until these few brief years of antibiotics. It seems also that the present general vigor of adult humanity must be the result of this sort of natural immunization. It is a legitimate question to ask: may not future adults be considerably more susceptible to disease—including such almost-forgotten horrors as puerpural sepsis—if