384 PATHOGENIC MICROORGANISMS 



Upon suitable media colonies appear as extremely delicate, grayish, 

 opalescent spots, at the end of twenty to twenty-four hours. The sepa- 

 rate colonies do not tend to "confluence and have' slightly undulated 

 margins. Touched with a platinum loop their consistency is found to 

 be slimy or, sticky. In fluid media, growth takes place chiefly at the 

 surface and there is no general clouding. 



Resistance. — Cultures of gonococcus, if not transplanted, usually 

 die out within five or six days at incubator temperature. At room 

 temperature they die more rapidly. In the ice chest they may be kept 

 alive for somewhat longer periods. In this they differ from meningo- 

 cocci, which are always killed by temperatures approximating zero C. 

 In these respects, however, individual strains show much variation, some 

 cultures dying out after but a few hours' removal from the incubator. 



The resistance of the gonococcus to light and heat is very slight. 

 A temperature of 41° to 42° kills it after a brief exposure. Complete 

 drying destroys it in a short time, Incompletely dried, however, and 

 protected from light (gonorrheal pus) it may live, on sheets and cloth- 

 ing, for as long as eighteen to twenty-four hours.' 



It is easily killed by most disinfectant solutions ^ even when these 

 are highly diluted and seems to be almost specifically sensitive to the 

 various silver salts, a fact of therapeutic importance. 



Pathogenicity. — Gonorrheal infection occurs spontaneously only in 

 man. True gonorrheal urethritis has never been experimentally pro- 

 duced in animals. In human beings, apart from the common seats of 

 the infection in the male and female genital tracts, and in the conjunc- 

 tivae, the gonococcus may produce cystitis, proctitis, and stomatitis. 

 It may enter the general circulation, giving rise to septicemia ^ and, 

 secondarily, to endocarditis and arthritis. Isolated cases of gonorrheal 

 periostitis and osteomyelitis have been reported.* 



The common acute infections of the genito-urinary passages in man 

 are often followed by an indefinitely prolonged chronic infection, which, 

 though quiescent, may for many years be a source of social danger. 

 In children, especially females, the infection is not rare, and may 

 assume epidemic characters, traveling from bed to bed in institu- 

 tions. Such hospital epidemics can be stopped only by the most 

 rigid isolation. It is advisable, in view of this danger, to examine all 



1 Heiman, Medical Record, 1896. 



'Schaeffer und Steinschneider, Kong. Deut. Dermat. Gesells., Breslau, 1894. 

 3 Review of cases of Gon. Septicemia, Faure-Beavlieu, Thesis, Paris, 1906. 

 * Ullmann, Wien. med. Presse, 1900. 



