The study of epidemiology is awakening a greater interest, and enlisting larger efforts in its behalf, than ever before. In his History of Medicine, Garrison speaks of it even today as “the infantile science of epidemiology, just emerging from the descriptive stage.” The predisposing factors of many epidemics of the medieval period, such as the crowded condition and bad sanitation of the walled towns, “the squalor, misrule and gross immorality occasioned by the many wars, by the fact that Europe was overrun by wandering soldiers, students and [others], and by the general superstition, ignorance and uncleanliness of the masses”—many of these have gone, let us hope, forever. If some epidemic diseases have almost vanished, or at least become greatly modified in severity or distribution, there are, nevertheless, others still with us to take their victims, and consequently to demand renewed investigation.
