185 



furnished by the manufacturers, which says that the effects of laying 

 the virus will be apparent in eight to ten days. 



DANYSZ VIEUS. 



Twelve tubes of Danysz virus were sent to the laboratory for exam- 

 ination April 7 by the Independent Chemical Company, agent for 

 Danysz Virus Company (Limited) . The label stated " Keep in a cool 

 place and at above temperature; use before May 15, 1909." 



The virus was kept at 15° C. until April 13, when it was turned 

 over to Passed Asst. Surg. W. H. Frost, who made the following 

 tests : 



One tube opened. Cultures made on two agar tubes were found 

 to correspond in cultural characteristics with the bacillus of Danysz 

 virus as generally described. The remainder of the tube prepared 

 according to directions in accompanying circular, using stale dry 

 bread 2 ounces and suspension of the culture in normal salt solution. 



Series 1. Approximately equal parts, then fed to six white rats 

 in individual cages, they having not been fed for twenty-four hours 

 previously. Eats all ate greater part of infected food. 



Five rats of series 1 died within five to seven days and were 

 partly eaten before being removed from the cage. The pathological 

 changes in all cases were chiefly enlargement and congestion of 

 spleen and liver, and in some cases inflammation of small intestine. 

 In each case an organism was obtained, usually in pure culture, 

 from one or more organs, corresponding culturally and morphologic- 

 ally with cultures taken from original tube. 



Series 2. April 14: Rats all ate greater part of infected food. 

 Transferred to large cage containing nine other white rats. Nine 

 other white rats exposed to infection by being placed in a large 

 cage with the rats of series 1. Four of the nine rats of this series 

 died in four to seven days after eating infected rats. 



Pathological changes and results of cultures from internal organs 

 the same as with series 1. Autopsy and cultures impossible in one 

 case, where body was almost completely devoured. 



Series 3. May 5: Three of the six surviving rats (one from series 

 1, two from series 2) were placed in individual cages, deprived of 

 food for twenty-four hours, then fed each with one-third agar tube 

 cultures of Danysz virus (the same used in the original feeding) . All 

 three ate practically all the virus given. 



All three of these rats remain alive and well after two months. 



Summary. — Series 1 . Six rats each fed one-twelfth to one-sixteenth 

 agar culture Danysz virus. Five died within five to seven days. 



Series 2. Nine rats exposed to infection by being placed in cage 

 with series 1. Four died within eight to twelve days after death 

 of first rat of series 1. 



