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May 31, 1902


JAMA. 1902;XXXVIII(22):1431-1433. doi:10.1001/jama.1902.62480220017001e

One of the fields of largest promise to the medical investigator of the future is that which holds the secrets of attenuation and malignancy of germs which cause infectious diseases. While laboratory processes have shed some light on this interesting subject, the fact remains that diseases spring up, prevail for a time in mild, severe or malignant form, and finally disappear according to laws that, for all practical sanitary purposes, are yet unknown. On the first appearance of a disease, no one can tell whether it will prove to be sporadic or epidemic, benign or virulent, of widely extended or only local prevalence. Extreme virulence may stamp a brief sporadic outbreak, while a very benign infection may be widespread and of long duration. Or—as happens more frequently—these conditions may be exactly reversed. Nevertheless, the term "epidemic constitution" so long used by the older writers to explain these conditions, or rather