370 BACTERIA PATHOGENIC TO MAN 



Pavement epithelium is more difficult to infect than cylindrical. 

 The gonococcus gradually penetrates the epithelial layer and produces 

 inflammation of the connective tissue. 



Immunity. Immunity in man after recovery from infection seems to 

 be only slight in amount and for a short period if present at all. It is 

 known that the urethra in man or cervix uteri in woman may contain 

 gonococci which lie dormant and may be innocuous in that person for 

 years, but which may at any time excite an acute gonorrhoea in another 

 individual or, under stimulating conditions, in the one carrying the 

 infection. 



Duration of Infections and of Contagious Period. There is no limit 

 to the time during which a man or woman may remain infected with 

 gonococci and infect others. We have had one case under observation 

 where twenty years had elapsed since exposure to infection, and yet the 

 gonococci were still abundant. It is now well established that most of 

 the inflammations of the female genital tract are due to gonococci, and 

 the majority of such infections are produced in innocent women by 

 their husbands who are suffering from latent gonorrhoea. 



Bacteriological Diagnosis of Gonorrhoea. In view of the fact that 

 several non-gonorrhoeal forms of urethritis exist, and also that micro- 

 cocci morphologically similar to the gonococcus Neisser are often 

 found in the normal vulvovaginal tract, it becomes a matter of great 

 importance to be able to detect gonococci when present, and to differ- 

 entiate these from the non-specific organisms. Besides this, the gono- 

 cocci which occur in old cultures and in chronic urethritis of long 

 standing sometimes take on a very diversified appearance. From a 

 medicolegal and social standpoint, therefore, the differential diagnosis 

 of the gonococcus has in certain cases a very practical significance. 



There are two methods of differential diagnosis now available 

 the microscopic and the cultural. Animal inoculations are of no 

 value, as animals are not susceptible, and, of course, human inocula- 

 tions are generally impossible. In the microscopic diagnosis it should 

 be borne in mind that after the acute serous stage has passed, the spe- 

 cific gonococci in carefully made preparations are always found largely 

 within the pus cells. Diplococci morphologically similar to gonococci 

 occurring in other portions of the field and outside of the pus cells 

 should not be considered specific by this test only. It should also be 

 remembered that the gonococci are decolorized by Gram's method, 

 while other similar micrococci which occur in the urethra are, as a rule, 

 at least not so decolorized. Organisms having these characteristics 

 can for all practical purposes be considered as certainly gonococci 

 if obtained from the urethra. From the vulvovaginal tract the cer- 

 tainty is not so great, since other diplococci are occasionally found in 

 gonorrhceal pus from the vulvovaginal tract, and very rarely, also, 

 from the urethra, which do not stain by this method; here cultures 

 should also be made. Cover-glass preparations from subacute or 

 chronic cases should be examined, if possible, with a microscope pro- 

 vided with a mechanical stage, and films should always be stained by 



