462 CHRONIC INFECTIOUS DISEASES 



phenomena, these diseases were extremely important to 

 consider. However, we have now available several accurate 

 methods of diagnosis. When doubt exists in clinical cases 

 or when there is no clinical evidence of the disease, although 

 the patient has been exposed, the following methods of 

 diagnosis may be employed. 



A. The Mallein Tests. — Mallein may be employed in 

 several different ways: 1. It may be injected into the skin 

 of the eyelid (intradermic, intrapalpebral) . 2. Instilled into 

 the conjunctival sac (ophthalmic). 3. Applied subcuta- 

 neously (hypodermic). 4. Rubbed into a disinfected area of 

 the scarified skin (endermic). The intradermic method seems 

 to be the most accurate and reliable and has been officially 

 adopted by the armies of the world. 



1. The intradermic method consists in injecting a special 

 mallein into the skin of the lower eyelid about one-quarter 

 of an inch from the margin and midway between the inner 

 and outer canthus and parallel with the lid. The best syringe 

 for this purpose is of the Luer type with glass barrel and 

 colored glass piston and of either | or 1 c.c. capacity, gradu- 

 ated in tenths and holding five to ten doses. The syringe is 

 fitted with a slip needle of 25 gauge diameter and approxi- 

 mately one-quarter of an inch long. The dose is j-^ of a c.c. 

 of intradermic mallein. The method of application is as 

 follows: With the left hand encircle the right eye with the 

 thumb and fingers, drawing the skin of the lower lid down 

 tightly with the thumb and allowing the fingers of the hand 

 to be free so as to act as a covering for the eye. With 

 the syringe in the right hand, the back of which is resting 

 against the head of the animal in order to follow any move- 

 ment, the needle may be introduced into the skin from before 

 backwards and parallel with the margin of the lower lid. 

 The free index finger of the right hand is then placed on the 

 end of the plunger and yV of a c.c. is injected. As the 

 mallein is injected, a small elongated swelling is seen to appear 

 within the skin, which insures that the injection has been 

 made into the dermis and not subdermally. The injection 

 may be made in either eye, the relative position of the 

 operator, assistant and animal remaining the same. While 



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