[The characteristics of a Russian-made kit for the serological identification of streptococci groups A, B and C].

The first Soviet kits for the serological identification of streptococci, groups A, B, and C, on the basis of the coagglutination test were developed. Each kit was intended for 35-40 determinations. The optimum concentration of streptococci during their identification by means of the reagents making up the kit was about 1.

[The effect of sodium nucleinate on the population characteristics of Streptococcus groups A and C].

The influence of sodium nucleinate on the growth kinetics, streptokinase activity and virulence of streptococcal populations, groups A and C, was studied. As revealed in these studies, the kinetics of the growth of the populations of both strains in the exponential phase did not depend on the concentration of sodium nucleinate in the culture medium. Measurements made on hours 15, 20 and 24 of growth showed the presence of close, direct and statistically significant correlation between the content of biomass, as well as streptokinase activity and specific streptokinase activity, and the concentration of sodium nucleinate in the culture medium.

[The formulation of epidemiological hypotheses by using the methods of multivariate statistical analysis].

The work demonstrates the main approaches to the use of the methods of multidimensional analysis for the creation of a hypothesis on the mechanism of the epidemiological process of dysentery in organized groups. The main risk factors have been established, and their role in the formation of annual, all-the-year-round and seasonal dysentery morbidity has been quantitatively evaluated. The results of analysis show the existence of diverse variants of the alimentary route of the transmission of infection, maintaining the epidemic process of dysentery, and the necessity of differentiating measures for the prophylaxis of all-the-year-round and seasonal morbidity.

[Phase changes in the population of group A streptococci and their influence on the course of the epidemic process of tonsillitis].

This work presents the data on the complex evaluation of the population of group A streptococci, studied at each of four phases (reservation, epidemic transformation, epidemic spread, reservational transformation) of the course of the epidemic process of streptococcal infection of the respiratory tracts (tonsillitis) in an organized group of adults. The characterization of the phases of the infective agent in accordance with the level of the carrier state, the size of streptococcal foci and the virulence of streptococci is given. Thus, the study shows that the heterogeneity of group A streptococci with respect to their virulence reaches its maximum level at the phases of reservation and epidemic spread and its minimum level at the phases of epidemic and reservational transformation.