IOWA ACADEMY OF SCIENCES. 201 



Diphtheria is a Greek word which means skin. Its chief 

 characteristic is a grayish-yellow membrane on the tonsils and 

 other parts of the throat. This disease is endemic in large 

 cities and more prevalent now than ever before . 



Diphtheria is very contagious, being communicated not only 

 by persons having it, but in various ways by persons who have 

 it not, but who have been exposed to the disease by association 

 or contact. Children and young people in delicate health or 

 having enlarged tonsils are most susceptible to it. 



The Klebs-Loefiier bacillus is always present in the exudate 

 during diphtheria. It is non-mobile, from 1.5 to 6.5 micromil- 

 limeter in length and from .3 to .8 of a micromillimeter in 

 thickness. It is rod-like with rounded ends. It grows best on 

 a mixture of glucose, bouillon, and blood serum at the temper- 

 ature of the human body, and forms on the surface of the cul- 

 ture medium large grayish-white colonies. 



This germ is occasionally found in the mouths of healthy 

 persons when an epidemic prevails; but no matter how badly 

 the throat may be diseased it is not diphtheria if, by repeated 

 and careful examination, the Klebs-Loefiler bacillus cannot be 

 found. These germs do not enter the blood. They are not 

 found in any of the organs of the patient having diphtheria. 

 Although this disease rapidly destroys more or less of the 

 mucous membrane lining the air-passages, yet the greatest 

 mischief is due to poisoning the blood, and the virus causing 

 this condition is called toxin. 



Dr. Edward Jenner, 100 years ago, discovered that immunity 

 from smallpox can be secured with cowpox virus, but only five 

 years ago was it found that the serum of the immunized horse 

 will both prevent and cure diphtheria. This medicine is called 

 anti-diphtheretic serum, also antitoxin. 



Parke, Davis & Co., the famous pharmaceutical manufac- 

 turers of Detroit, have stables in which are kept heifers from 

 which bovine virus is obtained, and horses from which anti- 

 diphtheretic serum is procured. The sero-therapeutic method 

 of treating diphtheria is a great discovery. This way of curing 

 diphtheria has only been in use four years. The remedy is 

 administered with a hypodermic syringe. 



Prior to the antitoxin period the average case mortality in 

 hospital and private practice in Chicago was about 35 per cent. 

 In 1896 this was reduced to about 20 per cent, or a little more 

 than three times greater than the mortality shown in the cases 



