[New laboratory test for the study of post-vaccination immunity and evaluation of the protective capacity of intestinal typhus vaccines].

Experiments were conducted on random-bred albino mice; the data of Dien et al on development of an infectious process in infection with a hybrid S. typhimurium strain No. 42 (with an antigenic structure of 0 divided by 9, 12; Vi; H: d; 1,2) were confirmed. Experiments of an active protection in infection with a hybrid S. typhimurium No. 42 strain permitted to investigate the intensity of antiinfectious immunity in mice. There were determined optimal conditions for laboratory experiments with a hybrid strain for assessment of the protective capacity of typhoid vaccines. In difference from experiments with S. typhi infection, under conditions of a model infection of mice, there was revealed a higher immunogenicity of an international reference-vaccine (L-WHO) in comparison with the antigen prepared by pancreatic digestion.