[Determination of the optimal inoculation dose of Brucella chemical vaccine].

Brucellosis chemical vaccine, when injected intramuscularly, proved to be low-reactogenic, postvaccinal reactions, both systemic and local, becoming less frequent and intense with the decrease of the dose from 2 to 0.5 mg. The highest antigenic and immunogenic activity was observed with a dose of 1 mg; out of 4 tested doses this dose produced the highest percentage of seroconversions, the highest titers of agglutinins and the longest time of their persistence in the subjects. When introduced in doses of up to 2 mg, brucellosis chemical vaccine did not induce pronounced sensitization. A high degree of correlation between the indices of seroconversion frequency in Wright's agglutination test and Huddleson's test was established after vaccination with all tested doses. This fact indicates that one of these tests can be used for the assessment of the antigenic and immunogenic activity of the vaccine at an early period after immunization (the term of observation not exceeding 3 months). On the basis of the complex comparison of the indices characterizing the reactogenicity and the antigenic and immunogenic activity of 4 tested doses of brucellosis chemical vaccine a dose of 1 mg was chosen as the optimum vaccination dose.