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Tick-borne encephalitis (TBE) remains one of the major public health concerns in northern Eurasia, and its' area is expanding. TBE virus (TBEV) includes three subtypes and several monophyletic groups, cocirculating in Russia. Five inactivated vaccines are used for TBE prophylaxis. The rising number of people subjected to vaccination brings up the issue of the impact of individual recipient characteristics on vaccination efficacy. The present work studies correlations among the vaccination scheme, sex, age, body mass index (BMI), chronic diseases, postvaccinal reaction, pre-existing anti-TBEV antibodies, and postvaccinal humoral immunity development. Sera were collected during clinical trials in the TBEV Siberian subtype endemic area. Adult recipients were vaccinated with Tick-E-Vac and EnceVir vaccines based on Far-Eastern TBEV strains. Vaccine ability to induce humoral immunity in different categories of recipients was estimated by seroconversion rates and the percentage of recipients with high neutralizing antibody titers (≥1:500). High immunogenicity of vaccines based on Far-Eastern TBEV strains in the TBEV Siberian subtype endemic area in all groups of recipients was demonstrated. Impact of pre-existing contact with the virus and high BMI on humoral immune response development 14 days after the first immunization was evidenced. Nevertheless, the difference was significantly less pronounced 30 days after the first vaccination and undetectable after the second one., (© 2018 Wiley Periodicals, Inc.)

In this study, we assessed in humans the immunogenicity and safety of one dose (7.5 or 15 μg of hemagglutinin [HA]) of a whole-virion inactivated prepandemic influenza vaccine adjuvanted with aluminum hydroxide. The vaccine strain was made by reverse genetics from the highly pathogenic avian A/Chicken/Astana/6/05 (H5N1) clade 2.2 strain isolated from a dead bird in Kazakhstan. The humoral immune response was evaluated after a single vaccination by hemagglutination inhibition (HI) and microneutralization (MN) assays. The vaccine was safe and immunogenic, inducing seroconversion in 55% of the evaluated patients, with a geometric mean titer (GMT) of 17.1 and a geometric mean increase (GMI) of 3.42 after a dose of 7.5 μg in the HI test against the vaccine strain. The rate of seroconversion increased up to 70% when the dose of 15 μg was used. The percentages of individuals achieving anti-HA titers of ≥1:40 were 52.5% and 57.5% for the 7.5- and 15-μg dose groups, respectively. Similar results were obtained when antibodies were analyzed in an MN test. Substantial cross-neutralization titers (seroconversion in 35% and 52.5% of subjects in the two dose groups, respectively) were detected against heterologous clade 1 strain NIBRG14 (H5N1). Thus, one dose of this whole-virion prepandemic vaccine adjuvanted with aluminum has the potential to be effective against H5N1 viruses of different clades.

Aim: Study dynamics of IFNalpha, IFNgamma, TNFalpha cytokines in healthy adults after administration of inactivated subunit monovalent influenza vaccine, A/California/7/2009 (H1N1) strain., Materials and Methods: Levels of IFNalpha, IFNgamma, TNFalpha cytokines were studied in blood sera of 58 mostly healthy adults aged 18 - 60 years. Kits for enzyme immunoassay determination of cytokine levels (Vector-Best, Novosibirsk) were used in the study. Antibody titers to A/California/7/2009 (H1N1) strain were determined at analogous time by using microneutralization reaction (MNR)., Results: Changes in the level of IFNalpha, IFNgamma, TNFalpha in healthy volunteers immunized by pandemic influenza vaccine were evaluated. Vaccine was safe. Two immunizations did not result in an increase of TNFalpha level that is an additional evidence of vaccine safety. IFNalpha level had a tendency to increase in vaccinated volunteers. IFNgamma levels in volunteers with normal level of this cytokine (below 10 pg/ml) were increased significantly after the second immunization (from 2.66 +/- 2.48 to 5.21 +/- 2.56). Correlation analysis showed that there is a strong negative association between IFNalpha, IFNgamma and seroconversion.

The quality of drugs used in the Russian Federation to prevent and diagnose tick-borne encephalitis (TBE) was analyzed. The TBE vaccines made in Russian were shown to be as effective as those manufactured in foreign countries and to have the similar production techniques and quality indices therefore they may be interchangeable in the population's vaccination. The specific activity of has recently increased in terms of the content of TBE virus antibodies. In Russia, a wide range of enzyme immunoassay systems have been designed and manufactured for the detection of human serum (plasma) IgM and IgG antibodies to TVE virus and for that of TBE viral antigen in the biological objects, primarily in the ticks.

Influenza remains a serious health problem, annually causing epidemics embracing up to 10% of the population of the world, and at the periods of pandemics this number may rise 4- to 6-fold. In the overwhelming majority of the countries the prophylaxis of influenza is carried out at present out with the use of inactivated vaccines. One of such vaccines is the highly purified split vaccine Vaxigrip (Aventis-Pasteur, France), permitted for use in Russia since 1992. The article contains the review of the data of literature, as well as the materials provided by the authors, which indicate that the preparation has low reactogenicity (also for children starting from the age of 6 months) and high reactogenic properties, leading to antibody formation at protective levels with respect to all three components of the vaccine. The vaccine has been found to ensure pronounced prophylactic efficacy for 70-90% of vaccinees and a decrease in influenza morbidity even in case of using the preparation a week before the onset of the epidemic. This shows the advantage of Vaxigrip in comparison with other inactivated vaccines.

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.

Tick-borne encephalitis is usually caused by infection with one of two flaviviruses: Russian spring summer encephalitis virus (RSSEV) or Central European encephalitis virus (CEEV). We previously demonstrated that gene gun inoculation of mice with naked DNA vaccines expressing the prM and E genes of these viruses resulted in long-lived homologous and heterologous protective immunity (Schmaljohn et al., 1997). To further evaluate these vaccines, we inoculated rhesus macaques by gene gun with the RSSEV or CEEV vaccines or with both DNA vaccines and compared resulting antibody titers with those obtained by vaccination with a commercial, formalin-inactivated vaccine administered at the human dose. Vaccinations were given at days 0, 30, and 70. All of the vaccines elicited antibodies detected by ELISA and by plaque-reduction neutralization tests. The neutralizing antibody responses persisted for at least 15 weeks after the final vaccination. Because monkeys are not uniformly susceptible to tick-borne encephalitis, the protective properties of the vaccines were assessed by passive transfer of monkey sera to mice and subsequent challenge of the mice with RSSEV or CEEV. One hour after transfer, mice that received 50 microl of sera from monkeys vaccinated with both DNA vaccines had circulating neutralizing antibody levels <20-80. All of these mice were protected from challenge with RSSEV or CEEV. Mice that received 10 microl of sera from monkeys vaccinated with the individual DNA vaccines, both DNA vaccines, or a commercial vaccine were partially to completely protected from RSSEV or CEEV challenge. These data suggest that DNA vaccines may offer protective immunity to primates similar to that obtained with a commercial inactivated-virus vaccine., (Copyright 1999 Academic Press.)

The results of the study of the effectiveness of using vaccine Vaxigrip for the prophylaxis of influenza in organized groups of adults are presented. The vaccine was found to have high epidemiological effectiveness (the epidemiological index was 2.6), moderate reactogenicity and pronounced immunological activity (the protection level was 89.0-100.0%). The vaccine may be recommended for the prophylaxis of influenza among adults.

The results of the study of the reactogenicity, safety and immunological activity of Russian cultural vaccine against hepatitis A are presented. The vaccine was found to have specific safety, moderate reactogenicity and pronounced immunological activity. In addition, the study of the prophylactic efficiency of the vaccine in the pre-epidemic period of the outbreak of hepatitis A morbidity in a group exceeding 14,000 adults was carried out. The study revealed high prophylactic efficiency of the vaccine (its efficiency rate was equal to 97.7%). On the basis of materials thus obtained vaccine "Hep-A-in-Vac" was recommended for use in medical practice for the prophylaxis of hepatitis A among adults.

During three seasons at the period of 1992-1996 immunization of elderly persons, living in homes for old people, against influenza with inactivated influenza vaccine (IIV) was carried out. Altogether 856 persons were immunized intranasally, 581 persons constituting the control group. For comparison, 4,825 healthy young adults aged 18-24 years were immunized under similar conditions. The study revealed that the intranasal immunization of elderly persons with IIV, made in two administrations, was safe and stimulated sufficient humoral and secretory immunity: the level of seroconversions was 24.3-41.0% to type A(H1N1) influenza virus, 29.6-50.7% to type A(H3N2) influenza virus, 39.3-59.6% to type B influenza virus; the level of diagnostic IgA conversions was 31-38%. Immunization produced a pronounced prophylactic effect (the effectiveness index 1.6-1.7), as well as decreased the total mortality level by half. The tactics of the immunization of persons from high risk groups against influenza in medical practice is discussed.

Inactivated culture vaccine against tick-borne encephalitis (TBE) FSME-Immun-Inject produced in Austria ("Immuno") was compared to vaccine produced in the Institute of Poliomyelitis and viral encephalitis by immunological activity, safety, reactogenicity. In mice, no significant differences in protective activity of the vaccines were found when test-strains were diverse strains of TBE virus. Seroconversion in the sera from the vaccinated two times was not significantly different by the level of antibodies determined for both eastern and western serotypes of TBE virus.

Schoolchildren of 30 to 34 schools of Novgorod were vaccinated over a three-year period with Russian live cold-adapted attenuated vaccine for children and whole-virus inactivated vaccines and placebo for comparative field study of the vaccines properties and efficacy. In control trials both bi- and trivalent live attenuated vaccines were well tolerated and areactogenic. A whole-virus inactivated trivalent vaccine induced mild and moderate fever and local reactions in 2-4% of the vaccinees. Special observations are necessary to establish the possibility of use and to determine a dose of this inactivated vaccine for immunization of children, especially those of 7-10 years of age. All the vaccines induced HI antibody production in 50-80% and antineuraminidase in 50-70% of seronegative children. The pattern of the results was similar to that in revaccinated children with preexisting antibody at a level of 1:20, but much lower in children with the initial titre above 1:20. After the 3rd year of vaccination the immune response of the vaccinees was similar, most of the results depending on the initial antibody titre and also on the change of vaccine strains. This raises a question of the expediency of annual influenza revaccination of the same person after 2 years of successful immunization and of the necessity of vaccine strains replacement after 2-3 years of use.

The article analyses the results of controlled epidemiologic observation made in military unit to estimate the immunological and clinico-epidemiological efficiency of national inactivated influenza vaccines with different valency and antigen charge in inoculative dose. The analysis proves the high immunogenic activity and protective features of inactivated influenza trivaccines with enhanced contents of hemagglutinins. The article substantiates the reasons for mass application of these vaccines in military units with obligatory addition of B-component and enhanced antigen contents of vaccine viruses in inoculative dose.

In a strictly controlled epidemiological trial on 12,643 school children aged 11-14 years the reactogenic properties and safety of killed influenza chromatographic vaccine under the conditions of multiple immunization were studied. A single immunization dose of the vaccine (0.2 ml) contained the hemagglutinins of influenza viruses A/Philippines/82 (H3N3) and A/Kiev/59/79 (H1N1), 3.5 micrograms each. The preparation was introduced by means of a jet injector. The vaccine was shown to be clinically and immunologically safe under the conditions of the regular multiple immunization of children over the period of 4 years.