448 



ERYSIPELAS. 



This is a si3ecific contagious disease, characterized by spreading 

 dropsical inflammation of the skin and subcutaneous tissues, attended 

 by general fever. It differs from most specific diseases in the absence 

 of a definite period of incubation, a regular course and duration, and 

 a conferring of immunity on the subject after recovery. On the con- 

 trary, one attack of erysipelas predisposes to another, partly, doubt- 

 less, by the loss of tone and vitality in the affected tissues, but also, 

 perhaps, because of the survival of the inf ecti ng germ. It is no longer 

 to be doubted that the microbes found in the inflammatory product 

 are the true cause of erysipelas, as the disease can be successfully 

 transferred from man to animals and from one animal to another by 

 their means. This transition may be direct or through the medium 

 of infected l)uildings or other articles. Yet from the varying severity 

 of erysipelas in different outbreaks and localities it has been surmised 

 that various different microbes are operative in this disease, and a 

 perfect knowledge of these might perhaps enable us to divide erysipe- 

 las into two or more distinct affections. At present we must recog- 

 nize it as a specific inflammation due to a bacterial poison and closely 

 allied to septicaemia. Erysipelas was formerly known as surgical 

 when it spread from a wound (through which the germ liad gained 

 access) and medical ov idiopathic when it started independently of any 

 recognizable lesion. Depending as it does, however, upon a germ 

 distinct from the body the disease must be looked upon as one no mat- 

 ter by what channel the germ found an entrance. Erysipelas Avhich 

 follows a wound is usually much more violent than the other form, 

 the difference being doubtless partly due to the lowered vitality of the 

 wounded tissues and to the oxidation and septic changes which are 

 invited on the raw, exposed surface. As apparently idiopathic cases 

 may be due to infection through bites of insects, the small amount of 

 poison inserted may serve to moderate the violence. 



This affection may attack a wound of any part of the horse's body, 

 ' while apart from wounds it is most frequent about the head and the 

 hind limbs. It is to be distinguished from ordinary imflammations 

 by its gradual extension from the point first attacked, by the abun- 

 dant liquid exudation into the affected part, by the tension of the skin 

 over the affected part, by its soft boggy feeling, allowing it to be 

 deeply indented by the finger, by the abrupt line of limitation between 

 the diseased and healthy skin, the former descending suddenly to the 

 healthy level instead of shading off slowly towards it, by the tendency of 

 tlie inflammation to extend deeply into the subjacent tissues between 

 and into the muscles and other structures, by the great tendency to 

 death and sloughing of portions of skin and of the structures beneath, 

 by the formation of pus at various different points throughout the 

 diseased parts without any surrounding sack to protect the surround- 

 ing structures from its destructive action, and without the usual 



