The fields of preventive medicine and public health have to a large degree been commingled, so that in the minds of many the terms are more or less synonymous. Some, however, wish to draw a clearcut line between the two. Many physicians seldom stop to think how much of their activity, and how many services they render to patients, are actually preventive in character. These services are usually rendered as remedial of illness and are, therefore, looked on as curative. It is difficult to differentiate clearly among public health, preventive medicine and curative medicine; indeed, it is neither necessary nor really desirable that sharp lines be drawn between them.
Public health is no longer concerned only with environmental factors that influence health. Preventive medicine is not limited to some few specific measures which when administered to individual persons will protect them against certain communicable diseases. Nor is curative medicine solely