INFECTIOUS DISEASES. 577 



10 to 14 (lays, the only sign left of the former swelling is a slight 

 thickening of the skin over the point of the injection; but at the 

 moment when the tension and temleniess of the parts at the seat 

 of inoculation become suddenly decreased a symptom of the utmost 

 clinical impt)rtance takes place, namely, at that moment the parasitic 

 of surra enters tlic blood of the general circulation. 



The temperature on the day of inoeulatiim, and, in fact, for several 

 days afterwards, may remain normal in character, there being oidy 

 a few degices dillcrence between tbi' morning antl evening observa- 

 tions. In other eases there may be a slight rise from the iirst even- 

 ing, and a gradual i)rogressive rise until the swelling at the .seat of 

 inoculation .slu)ws signs of reduction in size, when the temperature 

 generally takes a decided rise again, and ma}' attain 104° or 105.8° F. 

 This elevation will last a varying ])eriod of from two to six days, 

 and on the day following its ont>et the ordinary symptoms of fever 

 will be noticed, and in addition there will be petechia} on the con- 

 jinictival membranes, lacrinuition, a slight mucous discharge from 

 the nose, and in severe ca.ses some edema of the lower portion of the 

 legs, and perhaps of the sheath in horses. At the termination of the 

 period of fever the temperature Mill be found to have fallen to nor- 

 mal or nearly so; the animal will present a brighter aspect, and 

 there is every appearance of its return to health; in a few days, 

 however, the animal again appears didl and half asleep; the tem- 

 perature is elevated, a relapse takes place, and a repetition of all the 

 symptoms in the primary paroxysm, including the reappearance of 

 the parasite, is observed. 



Diaynos'is. — A diagnosis may also be established by the comple- 

 ment-fixation or agglutination tests with the sera from suspected 

 animals. This, however, can bo carried out only in laboratories and 

 requires special facilities for its execution. 



Treatment. — No s;itisfactorv treatment is known. Intravenous in- 

 jections of Fowler's solution of arsenic give temporary relief, but re- 

 lapses occur. In view of the great ec(>n(»mic importance of this 

 disease, it would not l>e advisable to attempt to treat any sporadic 

 ca.ses should they wcur in this country. On the contrary, the animals 

 should be slaughtered immediately and their carcasses promptly 

 burned. 



36444°— ir 37 



