756 INFECTION AND IMMUNITY. 



The organism was cultivated at autopsy from 

 the lung, testicle, cerebrospinal fluid, bile, parotid 

 gland and pericardial fluid. The coccus is a 

 Gram-positive organism occurring mostly in pairs 

 but also in short chains and small groups. It 

 varies from 0.5 to 0.8 microns in diameter in 

 twenty-four-hour cultures. It is non-motile, has 

 no capsule, and forms no gas or indol. It grows 

 slowly on ordinary media and much more rapidly 

 on media containing saliva. The growth on saliva 

 agar appears as pearly white pin-point discrete 

 colonies. 



Pathogen- The organism is fatal to white mice, white rats, 

 guinea-pigs and rabbits when injected subcutan- 

 eously; when injected into Steno's duct in mon- 

 keys and dogs non-suppurative parotitis was pro- 

 duced and occasionally an orchitis. The evidence 

 indicates strongly that the diplococcus described 

 by Herb is the specific etiologic factor in mumps. 



immunity. One attack usually establishes protection. Ac- 

 cording to Herb, the opsonins would seem to play 

 an important part in the protection of the body 

 against mumps. 



Patients should be isolated for three weeks 

 from the time symptoms appear. 



XIV. EPIDEMIC POLIOMYELITIS. 



Epidemic poliomyelitis, or acute anterior mye- 

 litis, is an acute febrile disease of children and 

 young adults accompanied by an acute inflamma- 

 tion of the cord and brain. Clinically, it is char- 

 acterized by paralysis of various muscles, usually 

 those of the extremities. The paralysis is very 

 rapid in onset and varies in tendency to recovery 

 and permanent disability. 



