52 BACTERIOLOGY FOR NURSES 



siderable length of time upon the bodies of healthy- 

 persons, and by them be transmitted to those who 

 are susceptible to infections, constitutes a serious 

 menace. The bacillus of influenza exists but a very 

 short time apart from its human host, but the bacilli 

 of tuberculosis and of typhoid fever are much more 

 resistant, adapting their existence to other conditions. 



Infectious materials are thrown off from the body 

 through the discharges from the nose, the mouth, 

 the intestines, the bladder, and the skin during the 

 course of infectious diseases, and are often found in 

 these tracts and in the excreta long after the patients 

 have seemingly entirely recovered ; this condition is 

 notable in diphtheria, scarlet fever, and tj^hoid 

 fever, and such persons are known as " carriers." 



The modes by which infectious materials are 

 carried from one person to another are at the present 

 time subjects for much discussion, and it seems to 

 be the consensus of opinion that " contact " infection 

 is much more frequent than was formerly supposed. 

 Contact does not necessarily imply the actual con- 

 tact of the sick and the well; for instance, the 

 child with diphtheria may leave infectious material 

 upon the drinking cup, or a clean wound may become 

 infected by contact with hands which carry infectious 

 material. 



