IN 1921 Modigliani and de Villa1 reported the production of papular erythematous reactions in children with whooping coughby intradermal injections of a simple autolysate of Hemophilus pertussis. Since then there have been numerous attempts to exploit hypersensitivity of the skin either as a diagnostic test or as a test of immunity. Allergic reactions either of the delayed (tuberculin) type or of the immediate type have been described. Comprehensive reviews of these trials and their conflicting results have been published by Thompson2 and by Lapin3.
The principal difficulty has been obtaining nontoxic material which does not produce local reactions in all persons, regardless of their history or contact with H. pertussis. Almost all whole cell suspensions or extracts thereof contain some toxic material (endotoxin). Therefore the erythema and induration produced may be either an inflammatory reaction to the toxin or an allergic reaction to the bacterial protein complex