[Immunologic reactions in man following oral immunization].

Prolonged clinico-immunological investigation was carried out on a volunteer; it was shown that a single oral vaccination with living B. citrobacter culture produced a marked immunological reaction in the form of increase of the typhoid Vi- and O-coproantibodies revealed in the fecal filtrate. The greatest rise of the preventive activity of the blood serum was noted after a 4-fold vaccination, whereas the maximum antibody formation--after a five-fold immunization in doses tested in the experiment. There was revealed no correlation (in time or intensity) between the three tests with the aid of which was the oral vaccination assessed.