Proposed standard agglutinating sera for typhoid and paratyphoid A and B fevers.

The preparation of seven Standard Agglutinating Sera considered suitable to serve as international standard preparations for use in the serodiagnosis of typhoid and paratyphoid infections are described, and proposals are made for their further examination on a collaborative international basis.Details are given of antigenic materials and immunizing procedures which should suffice to enable substandards, based on the proposed International Standards, to be prepared locally.With the aid of the proposed Standard Agglutinating Sera it is possible to determine the "Standard Agglutinin Titre" of a serum under examination by any technique of the agglutination test, provided that a suspension of average sensitivity is employed.