The practical value that the Schick reaction1 has acquired in the diagnosis of susceptibility or immunity to diphtheria makes it desirable to say a few words about the toxin used in the test, the overneutralized or the heated toxin used in the control test, about the technic of the test, and finally about the interpretation of the reactions.
The diphtheria toxin for use in the Schick test consists of a broth culture of the diphtheria bacillus, which has been grown in the thermostat at 37 C. for six days. To kill the living organisms 10 parts of a 5 per cent. solution of phenol (carbolic acid) (0.5 per cent.) are then added, and the bacteria allowed to sediment by keeping the broth culture in the ice box during the following two or three days. The supernatant culture fluid is now passed through a Berkefeld filter, and the clear filtrate
ZINGHER A. METHODS OF USING DIPHTHERIA TOXIN IN THE SCHICK TEST AND OF CONTROLLING THE REACTION: RESULTS OBTAINED WITH THE TEST IN 2,700 CHILDREN. Am J Dis Child. 1916;XI(4):269–275. doi:10.1001/archpedi.1916.04110100026003
Coronavirus Resource Center
Customize your JAMA Network experience by selecting one or more topics from the list below.