744 INFECTION AND IMMUNITY. 



until desquamation is complete. Disinfection 

 should be practiced. 



Susceptibility and virulence would seem to vary, 

 since the severity of the cutaneous lesions is not 

 constant. In delicate and tuberculous children, 

 the lesions may become gangrenous. Hemorrhagic 

 varicella is observed occasionally. Such compli- 

 cations as nephritis and otitis media occur. 



Varicella is a disease of childhood,, although it 

 may occur in adults. Infants are attacked less 

 frequently. Second or even third attacks occur, 

 although they are rare. 



There is no serotherapy. 



IX. SCARLET FEVER. 



The role which the streptococcus plays in scarlet 

 fever was considered on page 527. 



The "bodies" recently observed by Mallory may 

 be referred to briefly. 

 The Proto- In 1903 Mallory described certain protozoon- 



350011 (?) Of ,.- . ... ., -i . ,1 i nvi 



like bodies found in the skin of four cases. They 

 could be divided into two groups, one of which 

 consisted of "round, oval, elongated, lobulated 

 bodies" from 2 to 7 microns in diameter ; the indi- 

 viduals of the second group "contain a central 

 round body, around which are grouped, on optical 

 section, from 10 to 18 narrow segments, which, in 

 some cases, are united, but in others are sharply 

 separated laterally from each other." They occur 

 within and between the epithelial cells and in the 

 superficial part of the corium. He gives the name 

 of Cyclaster scarlatinalis to these bodies, and, al- 

 though expressing the belief that they are protozoa 

 and have a causal relation to scarlet fever, does not 

 claim to have proved such a relation. 



