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The authors studied the reactigenic properties, immunological and epidemiological efficacy of vaccination of children aged under one year by the experimental schemes (AKDC-AKDC-K -- 1 ml, and AKDC-AKDC-K -- 0.5 ml) in comparison with the official pertussis, diphtheria, and tetanus immunization scheme. There proved to be a greater immunogenicity and a better protective effect against pertussis in vaccination according to the experimental schemes. The vaccine reactions were somewhat more incident in children vaccinated according to the AKDC-AKDC-K -- 1 ml scheme, but their essential reduction was reached with reduction of the pertussis antigen third vaccination dose to 0.5 ml.

The authors analyzed epidemiological and clinical peculiarities of infectious hepatitis in children aged under 11 years in conditions of mass-gamma-globulin prophylaxis in microdoses the last 5 years in Voronezh. It appeared that the incidence of the disease fell and that its clinical course became milder. In connection with reduction of the incidence of infectious hepatitis in the age group of under 10 years, the incidence of the disease was relatively higher in children aged from 10 to 14 years, with a tendency to levelling-out the periodic autumno-winter elevations among preschool children. Introduction of decreased gamma-globulin dose for hepatitis prophylaxis led to a lesser expenditure of the preparation and thus permitted to vaccinate more children.

The results of weighing glass flasks before and after "shooting" preparations varying in viscosity into these flasks from type BI-3 jet injectors indicated that the ejected dose of gamma globulin corresponded to the preset value. Studies carried out by means of radioisotyope technique with the use of Tc99m showed that the intramuscular injection of gamma globulin with type BI-3 jet injector resulted in 75% of the preset dose penetrating the body. For this reason in mass vaccination against Botkin's disease the dose of the preparation in the injector should be increased by 1/3.

The present work deals with the controlled trial aimed at the study of the effectiveness of specific immunoglobulin against hepatitis A, developed in the USSR. This immunoglobulin is prepared from carefully selected blood sera from persons who have had hepatitis A. In accordance with the program approved by the USSR Ministry of Health, two trials were organized among the most susceptible groups of the population: organized groups of preschool children and young adults. During 6 months of the subsequent surveillance carried out in both age groups, the highest morbidity rate in hepatitis A was registered among the nonimmunized subjects. Morbidity rate among the subjects immunized with common commercial immunoglobulin was 3-7 times higher than among those immunized with the specific preparation, but a small size of the groups and a low morbidity level prevented the statistically significant confirmation of this higher effectiveness. Specific immunoglobulin produced a statistically significant (t = 2.72 and 2.4) decrease in morbidity rate among the immunized subjects in both age groups in comparison with morbidity rate among the nonimmunized ones.

Data are presented indicating that 1 ml of 10% and 1% immunoglobulin possessed similar epidemiological activity in the prophylaxis of infectious hepatitis. It was shown that redical action of infectious hepatitis on the epidemic process was possible only in case of embracement by immunoglobulin vaccination of not less than 80% of children aged from 1 to 11 years. The economic effect of the introduction of 1% immunoglobulin constituted about 40 000 roubles per 100 000 persons vaccinated. Besides, a possibility of side-effects were nilin case of placental immunoglobulin since in the 1% preparation nonspecific biologically active substances could penetrate in much lesser amounts.

The biological assay for the determination of HBsAg in gamma globulin is proposed. The assay is based on the immunizing action of immune complexes and some specific features of secondary immune response. For this purpose, the highly purified preparation of HBsAg is injected into guinea pigs. Subsequently the animals receive human gamma globulin. An increase in the titer of anti-HBsAg antibodies in the animals preimmunized with the antigen is indicative of the presence HBsAg in human gamma globulin. In accordance with another variant of this assay, human gamma globulin is introduced into mice and 21 days later the animals are immunized with HBsAg. The appearance of anti-HBsAg antibodies in the animals, previously treated with gamma globulin, on day 4 after the injection of the antigen indicate that the animals experience the second penetration of HBsAg, i. e. its presence in previously injected human gamma globulin.

The study of the effect of gamma globulin introduced in different doses (0.5 and 0.25 ml/mg) in combination with Fermi rabies vaccine (observations on humans were made) and with cerebral rabies vaccine inactivated by UV irradiation (in animal experiments) demonstrated that the injection of the higher doses of gamma globulin resulted in lower geometrical mean of antibody titers. Therefore, in combined administration of rabies vaccine and gamma globulin for postexposure rabies prevention it is advisable to reduce the dose of gamma globulin by one-half.

On the example of 4 cites of the RSFSR under conditions of expected epidemic threat a possibility was shown of directed influence on the viral hepatitis A epidemic process of preseasonal gamma-globulin prophylaxis conducted in 90% of "organized" children, aged from 1 to 12 years. The dose used was 0.75 ml of a 10% preparation. The method of Gorky Institute of Epidemiology and Microbiology was used to prognosticate the morbidity. It is recommended to improve the tactics of preseasonal gamma-globulin prophylaxis with consideration to the data of the viral hepatitis prognosis.

Various forms of interaction between diphtheria exotoxin and the continuous L and HeLa cell lines were revealed, depending on its doses: toxic, subtoxic and small (following the subtoxic dose). Cells of the same origin, treated with these doses, develop similar changes in some of their properties, differing only in their "survival" time, the period of adaptation and the time of entering the phase of active proliferation. The systems of cells, having simultaneously low susceptibility to infection with some RNA-containing viruses (L cells with low susceptibility to vesicular stomatitis virus and HeLa cells with low susceptibility to Coxsackie B5 virus) and high susceptibility to repeated treatment with diphtheria exotoxin, hve been obtained.

The immunogenicity, immunological and epidemiological effectiveness of the subcutaneous, enteral and combined immunizations of the workers at a steel plant with staphylococcal toxoid has been studied. The subcutaneous injection of the adsorbed toxoid in a dose of 0.2 ml by means of the jet injector, model, was accompanied by moderate reactogenicity (the frequency of local reactions was 26.8%, and the frequency of systemic reaction 18%) and produced 4-fold increase in antitoxin titers and 12-fold decrease in the morbidity rate of staphyloccal infection. Enteral immunization in 3 administrations proved to be nonreactogenic and only slightly effective (antitoxin titers increased more than 2-fold, morbidity rate fell 2-fold). Combined immunization (subcutaneous and enteral) with the toxoid, preceded by the injection of gamma globulin, reduced the frequency of reaction 2- to 3-fold and stimulated antitoxin production (the titer increased 8-fold), thus decreasing the morbidity rate of staphylococcal infection 3.1-fold.

The data provided by immunological and epidemiological studies carried out to determine the influence of the multiple injections of 10% commercial gamma globulin on the level of antigamma globulin formation and, in this connection, on the effectiveness of the prophylaxis of hepatitis A are discussed. A sharp increase in the titers of antigamma globulin in persons receiving multiple gamma globulin injections is shown. The increased amount of antibodies to gamma globulin, appearing as the result of the multiple use of this preparation, decreases the effectiveness of the seroprophylaxis of hepatitis A.