STUDIES ON HYPERSENSITIVENESS TO DIPHTHERIA BACILLI. I. AN "I~m~mAT~." SxrN REACTION WHICH CAN BE PASSIVELY TRANSFERRED

Hypersensitiveness of man to bacteria is of general importance because of its unknown effects upon infection and resistance and upon the manifestation of disease. From at least one aspect, hypersensitiveness to diphtheria bacilli seems to be especially important. While there are few diseases in which the manifestations can be referred so directly to the toxin, there are few pathogenic bacteria that are as widely distributed as the diphtheria bacillus. The question of hypersensitiveness to these bacteria, therefore, must be considered significant for it can be assumed that most city adults have probably had at some time in life such opportunities to become sensitive as may be afforded by contact with diphtheria bacilli. The present paper describes an "immediate" skin reaction to diphtheria bacilli, and presents experimental evidence to establish it as a true hypersensitive phenomenon distinct from the "delayed" skin reaction commonly encountered in Schick tests on adults ("pseudoreaction").