262 SPECIFIC MICRO-ORGANISMS 



thoughtful citizens, and it is already recognized as a sanitary 

 problem of the first magnitude. 



DiplocoGCUS Meningitidis (Neisseria Intracellularis). — Weich- 

 selbaum in 1887 examined the cerebrospinal fluid in six sporadic 

 cases oi meningitis and found in all of them a very definite Gram- 

 negative intracellular diplococcus, the meningococcus. He ob- 

 tained cultures but his animal inoculations all gave negative 

 results. Jaeger in iSq's seems to have found a similar organism in 

 fourteen, cases of epidemic meningitis and Huebner in 1896 ap- 

 parently found it in five cases. The cultural work of these authors 

 seems to be unreliable as their cultures were Gram-positive. 

 More conclusive confirmation of the relation of this organism to 

 epidemic meningitis was furnished by Councilman, Mallory and 

 Wright^ in 1918. 



The meningococcus is found in the bodies of patients suffering 

 from meningitis, occasionally on the nasal mucous membrane 

 of healthy persons and of cases of rhinitis, and very rarely in 

 other situations. In cerebrospinal meningitis the organism is 

 present in the cerebrospinal fluid, in the meninges, often on the 

 nasal and pharyngeal mucous membrane, sometimes in the 

 blood and on the conjunctivae, and rarely in the urethra, where 

 it may be mistaken for the gonococcus. It is usually found 

 without difficulty, in the cerebrospinal fluid in the first few days 

 of the disease, but may be very difficult to find at a later stage. 



The organism is found for the most part inside polynuclear 

 leukocytes and in its form, size, arrangement and behavior to 

 the Gram-stain resembles very closely the gonococcus. The 

 outline of the cocci is often somewhat hazy, suggesting possible 

 disintegration, and this sometimes makes their recognition 

 somewhat difficult in microscopic preparations of cerebrospinal 

 fluid. Cultures may be made on ascitic-fluid agar or blood agar, 

 upon which small dew-drop colonies appear in 24 hours at 37" C. 

 A better medium is obtained by laking human blood or rabbit's 



' Report of the Mass. Bd. of Health on Epidemic Cerebrospinal Meningitis, 

 etc., Boston, 1898. 



