The Pseudo-Schick Reaction and the Intradermol Toxoid Test of Moloney: their Relationship and Significance

Abstract

A total of 212 new members of the staff of the North-Eastern Fever Hospital were Schick and Moloney tested. The Schick-positive reactors were immunised with formol toxoid and post-Schick and Moloney tests were performed. The following conclusions were reached:(1) The intradermal toxoid test of Moloney or Zoeller corresponds exactly with the pseudo response in the Schick test.(2) The pseudo response is as efficient as the Moloney for detecting possible reactors to immunising doses of toxoid, and is a more accurate control of the Schick test. The Moloney therefore appears redundant.(3) A positive MP (Moloney or pseudo) reaction accurately indicates those who will react to immunisation; but a negative MP is no guarantee that the subject will not react.(4) The MP-reaction is evidence of bacterial hypersensitiveness to specific products of the body of the diphtheria bacillus.(5) Zoeller's theory that hypersensitiveness is a half-way stage between susceptibility and immunity, is incorrect.(6) MP-reactions usually, but not invariably, develop pari passu with immunity. Because of this parallelism tests of hypersensitiveness give information as to the state of immunity.The significance of tests of infection, hypersensitiveness and immunity are considered; and the possible relationship of MP-reactions with bacterial immunity suggested.