CHAPTER XXIII 



EXANTHEMATA 1 



UNDER this head are included measles, German 

 measles, scarlet fever, small-pox, chicken-pox, and 

 typhus fever. They are alike, in that no specific organ- 

 ism has yet been demonstrated and definitely proved to 

 be the cause of the infection. The causative agent is 

 spoken of as a " virus," and typic clinical symptoms 

 can be produced in healthy animals or humans by in- 

 oculation with skin or blood from patients ill with one 

 of the exanthematous diseases. 



Scarlet Fever. In 1904 Mallory described tiny 

 glistening corpuscles in tissue cells which he regarded 

 as the protozoan causes of scarlet fever. Other ob- 

 servers were unable to demonstrate them in living tis- 

 sues, but found them also in measles' blisters and in some 

 antitoxin rashes. They are now generally regarded as 

 degenerated leukocytes. 



Very recently (March, 1916) Mallory reports isolating 

 from the tissues of children dying early in the course of 

 the disease, especially from the tonsils, fauces, root of the 

 tongue, trachea and lungs, a strongly Gram-positive bacil- 

 lus growing between the epithelial cells. In form it varies 

 from coccus-like to large bacillary organisms. He believes 

 that this is the cause of scarlet fever, and has accordingly 



1 Exanthemata, the plural of exanthem = a breaking out, an 

 eruption. 

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