2 DAVID J. DAVIS 



I. INTRODUCTION. 



THE etiology of whooping-cough has not as yet been determined, 

 notwithstanding the large number of investigations upon this sub- 

 ject. The disease has many serious aspects, and the problem of its 

 etiology surely deserves to be ranked among the most important of 

 the still numerous problems concerning infectious diseases that so 

 far have not been solved. Like many other infectious diseases, the 

 therapeutics of whooping-cough is in a most unsatisfactory condition; 

 and it is likely to remain so, at least until the etiology is determined. 

 No specific is known, and while some drugs may mitigate the symp- 

 toms slightly, none has any appreciable effect upon the general course 

 of the disease. As regards its prevalence, it occupies a position in 

 the first ranks of the infectious diseases of children, probably being 

 equaled only by measles in this respect. While in strong, healthy, 

 and older children the disease may not be considered very serious, 

 however, owing to its prolonged course, especially in the winter 

 months, with an abundance of serious complications and sequelae, 

 it must be looked upon, as the high rate of mortality abundantly proves, 

 as one of the most dreaded diseases for the young infants and the 

 more delicate children. 



Reasons for assuming it an injections disease. There can be no 

 doubt that whooping-cough is an infectious, transmissible disease. 

 Several convincing reasons may be given for this. Transmission of 

 the disease certainly occurs by contact between children, and Baginsky 

 states positively that he has observed transmission by a third person. 

 There is no doubt that the virus adheres to rooms and fomites. The 

 frequent epidemic character of the disease, and its endemic character 

 in cities, indicate its infectious nature. Again, the disease has a 

 fairly definite period of incubation. There is some difference of 

 opinion as to the length of this period, but most observers agree that 

 it is from 7 to 14 days. Immunity is as a rule conferred by the attack. 

 Indicative of its infectious nature is also the relatively high leucocyto- 

 sis, which varies from 12,000 to 45,000, the increase in the mononu- 

 clears being particularly characteristic. Not only does the clinical 

 course of the disease indicate an infectious catarrhal condition of the 

 upper respiratory passages, but the pathologic anatomy substantiates 

 such a conclusion. The mucosa, especially of the larynx and trachea, 



