998 SOCIÉTÉ DE BIOLOGIE 



This method allows the distinct séparation of certain bacilli from 

 the diphtheric bacilli. But there are certain bacilli possessing ail the 

 characters of the diphtheric without being virulent. Those are the 

 ones which Loeffler has described under the name of psendo-diphtheric 

 bacilli. Thèse bacilli which are not virulent but possess ail the 

 characters of the diphtheric bacillus cannot be botanically separated 

 from the latter. Ail the others must be separated and cannot be called 

 pseudo-diphtheric. The rfght name for them seems to be that of 

 Corynebact.erium commune. 



P0^YEK OF CONTAGION. 



The most contagions carriers arc those suffering from the disease. 

 They hâve the most virulent bacilli and the mucosities of their throat 

 produce the greatest number of colonies when they are sowed on a 

 sérum. 



The consécutive cultures show a diminution of the colonies in pro- 

 portion with the time of onset of the disease. 



As a rule in al least 2/3 of the cases the bacilli hâve completely 

 disappeared one month after the beginning of the infection. 



The bacilli may persist for a very long time, more than from three 

 to six months; lliis seldom occurs. 



The forthcoming disappearance of the bacilli is indicated by : 1. The 

 diminution of Ihe colonies. 2. The decrease of virulence ; among 

 certain colonies examined certain kill a guinea pig in 2i or 36 hours, 

 others later, and olhers not at ail. h>en if they are not virulent 

 certain microbes possess ail tlic ciiaracters of the true diphtheric 

 bacillus ^growth in depth, fermentation of the glucose). 3. Other 

 microbes associate with thèse diphtheric bacilli and whereas the 

 colonies of diphtheric bacilli diminish there is an increase of staphylo- 

 cocci. The staphylooccus appears a few days before the disappearance 

 of the diphllieric bacillus. 



What is being said for the patient and the convalescenl is true for 

 the carrier. 



The contagious power of llie latter decreases with the number and 

 virulence of the microbe. 



Détection of tue carriers^ 



Carriers must be looked for in the surroundings of the patients. 



Among thèse are found early and récent carriers who are individuals 

 beginning to break out v^'ith diphtheria and bave been contaminated by 

 the patient. Those early carriers are seen in collectivities where 

 diphtheria has just appeared ; they are in the early stages of the 



