488 PLAGUE 



outstanding features. Usually, in the case of the dogs, a fatal 

 result followed after two or three weeks, and post mortem there 

 were found symptoms of catarrh of the respiratory tract and 

 sometimes patches of broncho -pneumonia, from which the bacillus 

 could be recovered in pure culture. The serum of the infected 

 animals gave the deviation of complement reaction. A specially 

 interesting fact is that a number of healthy young dogs contracted 

 the disease by contact with the inoculated. Fraenkel also 

 obtained positive results, closely similar to those of Klimenko, 

 on inoculation with pure cultures of the bacillus. 



The results of Bordet and Gengou have received general con- 

 firmation, although it is to be noted that Fraenkel and also 

 Wollstein failed to obtain the deviation of complement reaction 

 with the serum of convalescents. Bordet and Gengou have 

 inquired into this discrepancy in the case of the former, and find 

 that it depends on the nature of the culture medium used. At 

 present it is not justifiable to make a definite pronouncement on 

 the subject. We can only say that Bordet and Gengou have 

 made out a strong case for the etiological relationship of their 

 bacillus, and that their observations have been confirmed by 

 those of others. 



Methods of Examination. A portion of sputum expectorated 

 during a paroxysm of coughing should be obtained at as early as 

 possible a stage of the disease ; film preparations should be made 

 in the usual way and stained by carbol-thionin or carbol-methylene- 

 blue. If the characteristic bacilli largely preponderate, tubes of 

 the Bordet-Gengou medium may then be inoculated and in- 

 cubated. If there are numerous colonies of other organisms in 

 the tubes, a portion of the intervening agar should be scraped 

 with a needle and fresh tubes inoculated. As already said, 

 growth is at first very scanty but becomes more luxuriant in 

 sub-cultures. On pure cultures being obtained, the deviation of 

 complement test is to be applied by the method described (p. 131). 



PLAGUE. 



The bacillus of Oriental plague or bubonic pest was discovered 

 independently by Kitasato and by Yersin during the epidemic 

 at Hong-Kong in 1894. They cultivated the organism from a 

 large number of cases of plague, and reproduced the disease in 

 susceptible animals by inoculation of pure cultures. It is to 

 be noted that during an epidemic of plague, sometimes even 

 preceding it, a high mortality has been observed amongst certain 

 animals, especially rats and mice, and that from the bodies of 



