BIOLOGY IN HUMAM AFFAIRS 



The separate activities under public health research 

 work are so numerous and varied that it would be entirely 

 beyond the scope of this article to attempt an enumeration. 

 Possibly some reference to the classes of personnel employed 

 on this work may give an idea of its range. The United 

 States Public Health Service, for example, maintains 

 scientific workers of the following kinds: medical officers 

 specializing in a great variety of clinical, laboratory, and 

 field investigations; sanitary engineers, equally diversified 

 in interests; chemists — organic, analytical, physical, physi- 

 ological, biological, industrial, etc.; biologists — including 

 various specialists in microbiology, parasitology and 

 helminthology, entomology, planktonology, and lim- 

 nology; physicists specializing in various branches of 

 radiology, illumination, electricity, mechanics, etc.; bac- 

 teriologists and pathologists; sociologists, psychologists, 

 and psychiatrists; epidemiologists, statisticians, and math- 

 ematicians. These and other scientists, with their techni- 

 cians and assistants, make up a body of some three hundred 

 persons. The library personnel, also, must not be forgotten, 

 since it is essential in public health work to keep up with 

 the literature in one's specialty. 



Control operations of public health are a function of its 

 official organizations which occupy most of their time. 

 The "control" refers to the diseases which should be 

 checked or eradicated. Naturally, the first step is to know 

 where and in what numbers the cases of various disorders 

 are occurring. A bureau of vital statistics is required to 

 collect, classify, and arrange this material. Reports of 

 communicable diseases are secured from practicing physi- 

 cians, and are supplemented from various sources, such as 

 the records of school and industrial absenteeism and the 

 reports of visiting nurses. Then there are the birth and 

 death statistics to be recorded and analyzed. From this 

 mass of material, suitably tabulated and graphed, the 



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