COMMON COLDS 223 



not much poison, such pus and poison as are produced 

 being absorbed into the body without doing obvious harm. 

 At intervals, probably because of some disturbing influ- 

 ence that has affected the body, what is known as a 

 flare-up occurs, when the pus-formers multiply with great 

 rapidity and produce large quantities of pus and poison, 

 along with definite bodily symptoms of more or less 

 severity. After a longer or shorter period of activity, 

 the affected tonsil or ulcerated tooth quiets down and 

 gives little trouble for another period of time. Of recent 

 years, definite evidence has been secured that these low- 

 grade infections are responsible for acute rheumatism, 

 formerly called inflammatory rheumatism, which in turn 

 often results in valvular disease of the heart. Even 

 though such an acute trouble may not develop, bodily 

 harm is done, although the symptoms often come on so 

 gradually that the patient is unconscious that anything 

 is the matter with him other than that he seems to feel 

 continuously less fit and to be upset more readily than 

 formerly. The method of treating low-grade infections 

 is to get rid of the masses of organisms where the pus and 

 poison are being produced. Where the seat of infection 

 is the tonsil, this is accomplished by its simple removal. 

 It is not too much to say that the practice of dentistry 

 has been revolutionized within the last decade by the 

 recognition of the ease with which infection can establish 

 itself about the roots of the teeth, and of the frequency 

 with which such infection is reflected in distant parts of 

 the body as a result of the pouring out of poison from the 

 area of infection into the blood. 



Common Colds. — Probably the most common, arid 

 certainly the most frequently repeated infections from 

 which individuals suffer are those which cause common 

 colds. There are various reasons why colds are prevalent. 

 In the first place, it is now believed that there are 

 half a dozen or more different organisms which may cause 

 colds. Furthermore, all of them float about freely in the 



