The sensitivity of the skin to intradermal injections of diphtheria toxin in the Schick test is apparently less in the newly born than in older children, although there are certain discrepancies in the results reported. We wish to summarize these briefly and to report the results of a considerable series of tests in newly born infants and their mothers.
The first reported study was made by von Gröer and Kassowitz1 in Vienna, who found that 23, or 16 per cent, of 143 new-born infants had no demonstrable antitoxin in the cord blood, but only 7 of these (4.9 per cent) gave positive reactions to the Schick test.
Ruh and McClelland,2 in Cleveland, tested 100 mothers and their new-born infants and found a much higher percentage of positive reactions. Ninety-five mothers and their babies gave corresponding reactions; in 20 instances the reactions were positive in both mother and child,