The recognition of such a scourge as whooping-cough, particularly when occurring in institutions in which children are segregated in large numbers, is a matter of great importance.
In his address on this subject before this Society last year, Morse emphasized the difficulty—and the value—of early diagnosis.
By the time the paroxysmal stage is reached, the infection, where children are gathered together, is widespread, and the resulting mortality high, as shown by carefully collated statistics.
The desire to find a definite method of early diagnosis led us to a study of the complement-deviation test. With our modified technic we have been able to make the diagnosis of pertussis in all stages of the disease, catarrhal, paroxysmal and convalescent. Particular emphasis is laid on the point that the diagnosis can be made early in the catarrhal stage, long before any whoop appears, and at a time when prompt isolation of the infected