abstracts: bacteriology, epidemiology 87 



resembles culturally other members of this group, but serum tests are 

 capable of differentiating it from the other organisms worked with. 



J. W. Kerr. 



BACTERIOLOGY. — XVII. Further observations in rat leprosy. Don- 

 ald H. Currie, and Harry T. Hollmann, Public Health and Ma- 

 rine Hospital Service, Honolulu, T. H. Public Health Bulletin 

 50. 

 The authors refer to a previous article ("A Contribution to the Study 

 of Rat Leprosy," Public Health Bulletin No. 41, Public He lth and 

 Marine-Hospital Service of the United States, Washington, D. C, 

 November, 1910) in which they found that a broncho-pneumonia with 

 septicemia, due to the bacillus of rat leprosy, often preceded the better 

 known lesions of the disease. They further observed that a certain 

 mite (Laelaps echidninus) when found on the bodies of infected animals, 

 often contained the bacillus of rat leprosy. 



In the present article, they record further observations of a similar 

 character, and close by concluding as follows: 



"First: In the disease that we are dealing with, whether the animal 

 is inoculated by a laboratory method or simply allowed to develop the 

 disease from coming into contact with infected rats (i.e., the natural 

 mode of infection) the lesions met with are practically the same." 



"Second: With the exception of the local lesion, occasionally pro- 

 duced at the site of artificial inoculation, infection of the viscera seems 

 to usually precede the lesions of the skin." 



"Third: Of the visceral lesions, a broncho-pneumonia is often the 

 earliest, and the most constant. Infection of the spleen is also often an 

 early event." 



"Fourth: The heart blood of infected rats often contains the bacilli 

 of rat leprosy, and no difficulty is experienced in demonstrating the 

 presence of acid-fast bacilli in the mites, contained on the bodies of these 

 animals, when the latter's heart blood contains the organism." 



"Fifth: The fact that these mites contain the bacilli so frequently 

 naturally leads one to suspect that they may be one of the means of 

 transmitting the disease from rat to rat, but up to the present time we 

 have no positive evidence that such is the case." Donald H. Currie. 



EPIDEMIOLOGY. — The Causation and prevention of typhoid fever, 

 with special reference to conditions observed in Yakima County, Wash- 

 ington. L. L. Lumsden, U. S. Public Health and Marine-Hospital 

 Service. Public Health Bulletin 51. 

 The bulletin presents (1) a general consideration of the causation and 



prevention of typhoid fever with particular reference to conditions in 



