CHAPTER XV 



PREVENTION OF DISTRIBUTION OF CONTAGIOUS 

 DISEASES 



What are the diseases against which the housewife must 

 be on her guard lest they distribute themselves through 

 her home? They are evidently those due to microscopic 

 parasites, either bacteria or other forms of living things. 

 Not all forms of sickness are due to parasites, for some 

 have an entirely different cause. But the diseases with 

 which we are here concerning ourselves the so-called 

 contagious diseases, which are well known to be " catch- 

 ing " and which pass from the patient to a healthy indi- 

 vidual are due to parasites. 



The chief of these diseases are smallpox, scarlet fever, 

 diphtheria, measles, mumps, whooping cough, tonsilitis, and 

 influenza or grippe, all known to be contagious. In addi- 

 tion there are other diseases, serious but much less con- 

 tagious ; so slightly contagious, indeed, that until quite 

 recently they have not been looked upon as being capable 

 of passing from individual to individual. The most prom- 

 inent and important are typhoid fever and tuberculosis. 

 The best-known form of the latter disease is commonly 

 known by the name of consumption. Formerly neither 

 typhoid fever nor consumption was supposed to be con- 

 tagious, but it is now known that under some conditions 

 they pass from patient to healthy individual. Lastly 

 may be mentioned a class of diseases not in any proper 



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