Infections Agents. 73 



conditions) there are al\va\s a number of animals suffering from 

 the special infectious disease, so that others from these may in 

 turn acquire the affection. When an infectious disease occurs in 

 isolated cases here and there it is spoken of as a sporadic disease ; 

 if many or great numbers of individuals are affected, it is spoken 

 of as a plague, an epizootic {epidemic) ; if it extend over large 

 areas, 'and if not merely one species, but many, are aft'ected, it is 

 called a panzootic {pandemic). Animal diseases transmissible to 

 man may be spoken of as androzoonoses. 



The separation of spontaneous from contagious infections, the 

 recognition whether a microbe is miasmatic or purely contagious, 

 is of importance in dealing with epidemic diseases ; the purely 

 contagious diseases can be eradicated by measures protecting the 

 well from the diseased animals and their excrementitious matters. 

 This has been demonstrated in the extirpation of cattle plague, 

 pleuro-pneumonia and hydrophobia from districts in which for- 

 merly they were rife. 



SU^niARY OF THE AIOST IMPORTANT INFECTIOUS 

 DISEASES AND THEIR AGENTS.* 



I. Bacteriaemias, Septicaemias. 



Bacillus az'iscpticus [Boct. az'iscpticuin s. az'icidufu ) , septic:emia 

 of birds and rabbits (chicken cholera). 



Bac. pleuriscpticus, sporadic and epidemic septicaemia of all 

 domestic animals (bac. hoznscpticus, suiscpticus) , deer and cattle 

 plagues, pastcurcUosis hovis. 



Bac. antJiracis, anthrax of domestic animals and man. 



Bac. a\icn:atis nialigi:i, spreading gangrene of domestic ani- 

 mals and man. 



Bac. sarcoplixscuiafos boz'is. symptomatic anthrax of cattle. 



Bac. gastroinycosis czis, bradsot of sheep. [Bradsot is a dis- 

 ease of sheep in northern Europe, by man\' regarded as a form 

 of symptomatic anthrax.] 



Bac. pcstis iarandi, reindeer plague. 



Bac. rhusiopathicc suis, swine erysipelas. 



Bac. suipesfifer, hog cholera. 



Bac. pcstis buboniccr, human bubonic ])lague, transmissible to 

 swine and rats. 



*For detailed description and technique of investigations, v. Kitt, Bakterien- 

 kunde f. Ticrdrxtc, IV. Aufl., Wien, lOUo. 



