Since 1921 the literature has contained articles of interest on the subject of cutaneous testing for early diagnosis of whooping cough and for determining susceptibility or immunity to the disease. The reported results have been conflicting.
In 1934 Siebler and Okrent1 reported on a series of 186 subjects tested intracutaneously. The vaccine was prepared according to Sauer's technic (1933).2 It was found that 76 per cent of the subjects with a history of whooping cough gave negative cutaneous reactions and, conversely, that 80 per cent of those with no history of whooping cough had positive reactions. The readings were made after seventy-two hours.
On the other hand, Paterson, Bailey and Waller (1935),3 also using Sauer's vaccine, reported that children with a history of pertussis usually had positive cutaneous reactions, connoting immunity to the disease, while those with no history of whooping cough had negative reactions. The readings