The immunization of children with combined diphtheria and tetanus vaccine in Sweden

Two groups derived from 97 children three-four months of age were vaccinated with diphtheria and tetanus vaccines containing either a routinely prepared diphtheria toxoid or a more purified preparation. Two injections were given with an interval of one month and a third injection was given one year after the first. Prior to the third injection no child was without protection against diphtheria, i.e. had an antitoxin titre less than 0.01 IU ml-1. After the third injection 95 and 94% of the children vaccinated with the routinely and more purified diphtheria toxoids, respectively, had diphtheria antitoxin titres greater than 1 IU ml-1 (estimated to provide protection for at least ten years). Systemic reactions such as fever and malaise occurred in five children. Local reactions greater than 10 cm were observed in three children and reactions greater than 5 but less than or equal to 10 cm were seen in 14% of the children. The routinely prepared combined diphtheria and tetanus vaccine, DT, produced very good immunity against diphtheria with moderate side effects. The use of a more purified diphtheria toxoid in the combined vaccine produced the same immunity and side effects.     

A cultured concentrated inactivated vaccine against tick-borne encephalitis studied during the immunization of children and adolescents

The word deals with the results obtained in the study of the reactogenicity and immunological activity of concentrated and inactivated tissue-culture tick-borne encephalitis vaccine, manufactured by the Chumakov Institute of Poliomyelitis and Viral Encephalitides, in the immunization of children and adolescents. The vaccine proved to be moderately reactogenic and exhibited pronounced immunological activity. In 91.5% of the immunized children the fourfold increase of the antibody level was observed. On the basis of the data obtained in this study the tick-borne encephalitis vaccine was recommended for use in medical practice for the prophylaxis of tick-borne encephalitis among children and adolescents.     

Active immunization against Pneumocystis carinii with p55-v3 DNA vaccine in rats

Pneumocystis pneumonia (PCP) occurs predominately in patients with impaired immunity. Because standard PCP chemoprophylaxis and chemotherapies have limitations, immunotherapy, particularly vaccination, offers an attractive alternative approach for PCP prevention and treatment. The goal of this study was to evaluate the potential of DNA vaccines targeting two closely related antigens, p55-v0 and p55-v3, in an immunosuppressed rat PCP model. We found that immunization with p55-v0 and p55-v3 DNA vaccines afforded a similar level of protection to rats against PCP, as evidenced by significant reductions in organism burdens, improved histological scores, and lower lung weight to body weight ratios. Additionally, vaccination elicited both cellular and humoral immunity in immunosuppressed rats. Our data suggest the potential of p55 DNA vaccines to protect against PCP in rats. Future work should focus on epitope mapping and identifying protective moieties in each gene.     

Evaluation of influenza vaccine Vaxigrip in the combined immunization of conscripts during influenza seasons of 2002-2003

The immunization properties of the influenza vaccine Vaxigrip, used in combination with vaccines against pneunococcal infection and hepatitis A (respectively, Pneumo 23 and Avaxim), were evaluated. In Central Russia in one of the units of the internal forces of the RF Ministry of Internal Affairs 3 groups totaling 755 servicemen were formed, depending on the complex of the introduced vaccines. Active medical observation and the registration of the complaints of the vaccinees at the postvaccinal period did not reveal unusual reactions and complications in none of the groups under observation. In the evaluation of the level of specific antibodies to the circulating influenza viruses prior to vaccination the low level of collective protection to influenza B virus was determined: protective antibody levels were registered only in 14-18% of the servicemen, while the corresponding data with respect of influenza viruses A(H1N1) and A(H3N2) were 45-50% and 56-63% respectively. At the same time, in seronegative persons the vaccine Vaxigrip exhibited high immunogenic activity with respect of all 3 influenza strains; seroconversion to them was determined in 84-92% of the vaccines, and the level of protective antibody titers before the beginning of the epidemic season was 86-99% in the whole of the group. The characteristics of the prophylactic effectiveness of the vaccine Vaxigrip in relation to the influenza virus infection level 1 were 4.7 (index) and 79% (coefficient). In addition, the frequency of influenza cases, clinically pronounced and confirmed by laboratory methods, in patients who had been immunized with 3 vaccines was 6.7%, which was 10.3 times less frequent than number of cases in the groups of comparison (68.2% on the average). The coefficient of epidemiological effectiveness of the prophylaxis of influenza was 90.2%. The complex use of 3 preparations did not affect the immunization properties of the vaccine Vaxigrip.     

The characteristics of the development of immunity with a primary immunization complex using adsorbed DTP vaccine

The intensity of immunity, depending on immune response variants characterized by the definite composition of the T and B lymphocyte subpopulation in peripheral blood, was studied in 70 practically healthy young children after the primary complex of immunization with adsorbed DPT vaccine. The most stable immune reaction was shown to appear in children with the hyperergic and normoergic variants of immune response to diphtheria and tetanus toxoids, while the reaction to pertussis antigen was essentially weaker both after the second vaccination and after the first revaccination. In children with the hypoergic variant of immune response to all components of adsorbed DPT vaccine the resulting immune reaction was 2.5-3 times weaker than in children of other groups.     

Macrophage transformation of mononuclear cells following primary and secondary experimental immunization with measles vaccine

Cell-mediated and humoral immune response was studied in guinea pigs receiving two immunizations with live measles vaccine l-16 in doses of 1000 TCD50/0.5 ml at an interval of 45 days. The results of this study showed that the maximum level of the macrophagal transformation of mononuclears and the most intensive synthesis of antimeasles antibodies were observed on day 10 after booster immunization. The intensification of cell-mediated and humoral immune response was found to depend on the initial immunological background. The animals having had high values of cell-mediated response before booster immunization showed a decrease in these values, while an increase in antibody titers in such animals was transitory.     

Antidiphtheria immunity in children after immunization with adsorbed DPT vaccine and ADPT-M toxoid

Antidiphtheria immunity in children aged 3-15 years was evaluated, depending on their age, the vaccinal preparation chosen for immunization and the immunization schedule. Adsorbed DPT vaccine was shown to have a higher immunological activity in comparison with adsorbed DT toxoid with reduced antigen content. The relationship between the tension of antidiphtheria antitoxic immunity in children and the possibility of the formation of the clinical forms of diphtheria with different severity in the patients was established. Children aged 4-6 years were considered to be a group of high risk in diphtheria morbidity, as it was among the children of this group that toxic and subtoxic forms of diphtheria were most often registered (44.9 +/- 7.1% of the examinees); in addition, a high proportion of children seronegative to this infection (26,3 +/- 2.2%) was observed in this group.