The provisional international standard antityphoid serum.

The Provisional International Standard Antityphoid Serum, prepared in 1935, provided standards of the O and the Vi antibodies, both contained in a single serum preparation, and was used for standardizing the potency of therapeutic antityphoid serum.The "Provisional Standard Serum for Vi Agglutination", which is one of the series of proposed Standard Agglutinating Sera for Typhoid and Paratyphoid A and B Fevers, is based on the Provisional International Standard Antityphoid Serum.It is recommended that the Provisional International Standard Antityphoid Serum, in conjunction with a standard typhoid vaccine, be used in the test for the determination of the "functional efficacy" of the Vi antibody. This is one of the several tests recommended for the official control of the immunizing potency of typhoid vaccines.