124 SCIENCE REMAKING THE WORLD 



v 



and" focal reactions. A local inflammation is produced 

 at the site of injection, a general reaction characterized 

 by headache, backache, and fever, and a renewed or 

 increased activity at the site of injection. This latter 

 can readily be seen in lupus. Tuberculin was advocated 

 by Koch as a curative agent, but it has been proven 

 almost valueless and when not properly administered 

 does more harm than good. Koch announced that the 

 general reaction did not take place except in tubercu- 

 losis, but many observers soon found that healthy in- 

 idividuals reacted when larger doses were given. It 

 was found that sometimes 50 per cent, of adults reacted, 

 /and even 90 per cent, at times, depending on the size 

 of the dose. Its diagnostic value was therefore minim- 

 ized. Calmette and Wolff-Eisner found that tuber- 

 'culin dropped in the eye would produce a reaction. 

 Moro rubbed it into the skin and finally Pirquet in 1907 

 found that if a very slight abrasion were made in the 

 skin and a drop of tuberculin placed on the abrasion, 

 a local reaction would take place in tuberculous per- 

 sons, but without systemic or focal reaction. At first 

 this test was thought to be of great diagnostic value, but 

 as in the subcutaneous test it seemed that nearly every 

 one healthy or tuberculous reacted, with the exception 

 of very young children. Here was a phenomenon which 

 was difficult at first to accept; but Naegeli had shown 

 that 97 per cent, of adults autopsied showed an old 

 tuberculous process and many others had shown that 

 tuberculous lesions were rare in infants, but that as the 

 child grew older the lesions were more frequently found. 

 It is evident then that there was a marked difference 



