CHAPTER XXXV 



DISEASES OF UNKNOWN OR NOT DEFINITELY DETERMINED 



ETIOLOGY 



OF TEMPERATE CLIMATES 



Acute Articular Rheumatism. Various bacteria have been reported 

 as cause. The organism which seems the most probable cause is the 

 short chain coccus, Micrococcus rheumaticus of Triboulet and others. 

 Inoculations of this streptococcus cause polyarthritis and pericarditis. 

 Poynton and Paine have cultivated the organism from the cerebro- 

 spinal fluid in three cases where chorea was present. 



The Common Cold. Of all the diseases common in man this condi- 

 tion has been surrounded by greater etiological and epidemiological 

 obscurity than any other. 



We are inclined to believe that the common cold (coryza) sets in when our re- 

 sistance is lowered by alimentary tract disturbances, from exposure to variations 

 in temperature, or following refrigeration and fatigue. Of course, many have held 

 that the common cold was "catching" but the evidence offered in support of such 

 a view has been academic. 



Many bacterial organisms have been suggested as causative such as 

 B. coryza segmentosus, haemolytic and viridans types of streptococci, 

 M. catarrhalis, etc. In 1914 Kruse brought forward evidence to prove 

 that the etiological factor in coryza was a filterable virus. Quite re- 

 cently Foster has conducted experiments in which, by using the nasal 

 discharge from typical coryza cases, diluting it with 10 or 15 times its 

 volume of saline, then passing through a small Berkefeld filter and in- 

 stilling 3 to 6 drops of the filtrate into the nasal cavity of 10 well men 

 he produced typical coryza in nine of these men in from eight to thirty 

 hours. Cultures were made from the filtrate following Noguchi's 

 spirocha?te culturing method. The culture medium surrounding the 

 piece of sterile tissue showed turbidity in from forty-eight to seventy- 

 two hours and dark-field examination showed myriads of extremely 

 active bodies which were thought to possess true motility rather than 

 Brownian movement. 



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