[An evaluation of the epidemiological and immunological efficacy of the vaccinal prophylaxis of diphtheria and tetanus]. / Otsenka épidemiologicheskoi i immunologicheskoi éffektivnosti vaktsinoprofilaktiki difterii i stolbniaka.

The extensive use of adsorbed diphtheria-tetanus toxoid with reduced antigen content was found to be ineffective in the prophylaxis of diphtheria: 86.3% of diphtheria patients among those who had been immunized with this preparation fell only a year after the first booster immunization, and the proportion of those who proved to be unprotected against diphtheria on years 3, 4 and 5 after immunization reached, respectively, 21.0%, 35.5% and 49.4%. The number of children immunized with this preparation at common preschool institutions may reach 50% and more, and with an increase in the coverage of children with immunization from 10% to 50% the proportion of unprotected children may rise from 7.4% to 17.8%. The proportion of preschool institutions, insufficiently protected from diphtheria and, as a consequence, running a considerable risk of becoming (in case of the penetration of this infection) the foci of diphtheria, was found to reach 32.9%.

[A comparative evaluation of the effectiveness of methods for serological sampling examinations]. / Sravnitel'naia otsenka éffektivnost' nekotorykh metodov vyborochnykh serologicheskikh obsledovanii.

Blood serum samples of 3,448 schoolchildren of grades 1-10 in 35 schools of Dushanbe were examined in the passive hemagglutination test in 1988 and 1989. The proportion of persons unprotected against diphtheria and tetanus was estimated by common methods in different kinds of selective serologic survey: mass screening (43.4-83.0%), testing in selected groups reduced 2, 3 and 5 times, cluster sampling. The reduction of the groups to be examined (from 3,033 to 250 persons) was not accompanied by essential changes (t < 2) in the characteristics of mass immunity against diphtheria and tetanus. The cluster method was shown to be highly reliable also in the study of population immunity.

[The cytochemical marking of lymphocyte subpopulations in determining the immunoreactivity status of children vaccinated with a live measles vaccine]. / Tsitokhimicheskaia markirovka subpopuliatsii limfotsitov pri opredelenii sostoianiia immunoreaktivnosti u detei, vaktsinirovannykh zhivoi korevoi vaktsinoi.

In 54 children aged 1.5-2 years, immunized with the same batch of live measles vaccine prepared from strain, the relative and absolute numbers of different lymphocyte subpopulations were determined in parallel by means of two cytochemical reactions: for acid alpha-naphthyl acetate esterase and acid phosphatase in their dynamics. According to the data obtained in these reactions, the determination of lymphocyte subpopulations by two cytochemical methods in the same blood sample yielded similar results indicating that immunization with attenuated measles virus strain induced a rise in the number or zero lymphocytes and was accompanied by the decrease of the immunoregulatory index (T-helper/T-suppressor ratio), most pronounced in children with a high level of antibody formation.

[The results of an immunoepidemiological examination of foci of epidemic parotitis]. / Rezul'taty immunoépidemiologicheskogo obsledovaniia ochagov épidemicheskogo parotita.

The immunoepidemiological survey of 54 foci of epidemic parotitis showed that the epidemiological effectiveness index at preschool institutions, equal to 2.7, was essentially higher than at schools (2.1). The significant difference (t = 3.35) in the epidemiological effectiveness indices was due to the presence of a large number of persons having had inapparent and faintly pronounced forms of epidemic parotitis among school children, as well as due to more close contacts of children with the foci of infection at preschool institutions. The study showed that among children immunized with some lots of parotitis vaccine elevated morbidity in epidemic parotitis was registered. In the foci of infection children, immunized in the presence of low initial titers of specific hemagglutinins in their sera, responded by a booster effect with different duration of stimulation of antibody formation. The hemagglutinin titer of 1:20 was shown to protect children from epidemic parotitis.

[The duration and strength of postvaccinal measles immunity]. / Dlitel'nost' i napriazhennost' postvaktsinal'nogo protivokorevogo immuniteta.

A prolonged immunoepidemiological follow-up of a large group of children immunized against measles revealed a high epidemiological efficacy of a single vaccination. Cases of measles were registered only among those vaccinees in whose blood sera no specific hemagglutinins were detectable by titration with 4 hemagglutinating units of measles antigen prior to the disease. The study showed that groups of children seronegative with respect to measles appeared, as a rule, after unsatisfactory immunization and not due to loss of postvaccinal immunity with time. Properly immunized children in whom the formation of antimeasles antibodies had occurred in response to the injection of live measles vaccine retained postvaccinal immunity for more that 15 years (the term of observation).

[The duration and intensity of measles immunity after a repeat inoculation against this infection]. / Dlitel'nost' i napriazhennost' immuniteta k kori posle povtornoi privivki protiv étoi infektsii.

Controlled study lasting 6 years showed that booster immunization against measles was highly effective in children remaining seronegative, i. e. susceptible to this infection, after primary immunization: E = 97.5 +/- 0.12% (K = 35.7). Annual serological examination of children given booster immunization revealed that 87.6% of initially seronegative children retained specific antihemagglutinins for 5.5 years (the term of observation). The effectiveness of booster immunization against measles did not depend on the age when primary immunization had been made.

[The dynamics of the T-lymphocyte subpopulations and the peroxidase activity of the neutrophils in children immunized with a live mumps vaccine]. / Dinamika subpopuliatsii T-limfotsitov i aktivnost' peroksidazy neitrofilov u detei, immunizirovannykh zhivoi parotitnoi vaktsinoi.

The amount of T-helpers and T-suppressors and the T-helper/T-suppressor ratio were determined in 30 practically healthy children aged 1.5-2 years, immunized with live parotitis vaccine prepared from strain -3. One immunization dose of the vaccine contained 7,950 HADU50. In all children peroxidase activity in the cytoplasm of neutrophils was studied. This investigation revealed that in all examined children the formation of immune response to immunization with live parotitis vaccine was accompanied by the development of an imbalance of immunoregulatory T-cell subpopulations and by functional changes in neutrophils, characterized by the inhibition of peroxidase activity. The changes revealed in this study were most pronounced in children with a high level of antibody formation.

[Macrophage transformation of mononuclear cells following primary and secondary experimental immunization with measles vaccine]. / Makrofagal'naia transformatsiia mononuklearov posle pervichnoi i vtorichnoi immunizatsii korevoi vaktsinoi v éksperimente.

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.

[Prevention of mumps in preschool institutions using a live mumps vaccine made from strain L-3]. / Profilaktika épidemicheskogo parotita v detskikh doshkol'nykh uchrezhdeniiakh zhivoi parotitnoi vaktsinoi iz shtamma L-3.

The effectiveness of the emergency vaccinal prophylaxis of epidemic parotitis was studied in 19 children's day-care centers. As revealed in this study, the immunological effectiveness of vaccination did not depend on the age of vaccinees, but sharply decreased if live parotitis vaccine contained less than 10,000 HADU50 per immunization dose. After a single administration of the vaccine 91.1 +/- 0.98% of children were found to produce mumps antibodies. The immunization of children with live parotitis vaccine prepared from strain l-3 immediately after the first case of parotitis had been registered proved to be a highly effective measure. The coefficient of epidemiological effectiveness was 96.4%.

[Epidemiologic surveillance of diphtheria and measles]. / Epidemiologicheskii nadzor za difteriei i kor'iu.

The epidemiological surveillance of diphtheria and measles makes it possible to evaluate the actual coverage of different groups of population with immunization and the state of this protection, to determine the tendencies of the epidemic processes of the afore-mentioned infections, to assess the efficacy of prophylactic and antiepidemic measures, and to develop well-grounded recommendations aimed at preventing the formation of foci of group infections and the lethal outcomes of diphtheria and measles.

[Reactogenic properties and immunogenicity of measles and mumps vaccines when used by different procedures]. / Reaktogennye svoistva i immunogennost' korevoi i parotitnoi vaktsin pri razlichnoi taktike ikh primenenii.

In the controlled epidemiological trial the reactogenic and immunogenic properties of live measles vaccine (LMV) and live parotitis vaccine (LPV) were evaluated in identical groups of children immunized in accordance with different schedules: only LMV or LPV, the injection of these preparations mixed in one syringe or with the use of separate syringes, or at an interval of 3 months. The highest number of febrile reactions, rash and catarrhal symptoms was registered among children immunized with LMV, and the lowest number of such reactions in the groups of children immunized with LPV. The injection of LMV and LPV with one syringe or simultaneously with separate syringes decreased the intensity of immune response to the injection of the antigens. Immunization against measles and parotitis by the injection of monopreparations at an interval of 3 months is believed to be most expedient.

[Measles morbidity among children inoculated against this infection]. / O zabolevaemosti kor'iu privitykh protiv étoi infektsii detei.

In the serological survey of 2009 children immunized against measles 285 children (14.2%) were found to be seronegative to this infection in the hemagglutination inhibition test with 4 hemagglutinating units of the antigen. Among 1724 immunized children showing positive response to vaccination and placed under dynamic observation for 11 years, 2 cases of measles were registered. At the same time, in the dynamic observation of 111 seronegative children 66 measles cases (59.5%) were registered during the above period, while among 169 children, also seronegative, but receiving booster immunization against measles, morbidity rate was only 1.2%. In some vaccinees the decrease of postvaccinal immunity to seronegative values was observed, but such decrease had no essential influence on the morbidity level among the vaccines. The increase of measles morbidity among schoolchildren immunized against this infection was due not to the decrease of their postvaccinal immunity, but to their concentration in schools and to their more intensive contacts with the sources of infection in comparison with children of preschool age.

[Immunocytochemical indices of the measles vaccinal process]. / Immunotsitokhimicheskie pokazateli korevogo vaktsinal'nogo protsessa.

To study the immune responsiveness of children in the measles vaccinal process, the cytochemical methods for the identification of immunocompetent cells have been used. The investigations have been made in children aged 1.5-4 years, immunized with live measles vaccine prepared from strain l-16. The results of these investigations indicate that the development of specific antiviral postvaccinal immunity is characterized by transitory changes in the populations of T-, B- and O-lymphocytes; such changes are accompanied by not only quantitative, but also qualitative changes of individual populations.

[Immunostructure of school-age children inoculated against measles]. / Immunostruktura privitykh protiv kori detei shkol'nogo vozrasta.

The mass serological survey of school children immunized against measles was carried out by means of the hemagglutination inhibition test. As a result, 20.4% of these school children were found to be seronegative, and in 9.5% of them even the minimum concentration of measles antihemagglutinins (when titrated with 1 hemagglutinating unit of the antigen) was not detected. The accumulation of a considerable seronegative (measles-susceptible) stratum among children of school age occurred due to the low immunogenic potency of some batches of live measles vaccine, used for immunization in 1973, as well as due to the formerly practiced immunization of children under 1 year of age. A direct and close dependence of focal measles morbidity among immunized children having had contacts with the source of infection on the number of children among them, found to be seronegative after titration with 1 hemagglutination unit of measles antigen, was established.

[Immunological reactivity of children vaccinated with a live measles vaccine]. / Immunologicheskaia reaktivnost' detei pri vaktsinatsii zhivoi korevoi vaktsinoi.

Immunologic responsiveness in measles vaccinal and infectious processes was studied by the neutrophil alteration test in 72 children varying in ages from 18 months to 4 years of whom 20 were in the acute period of measles infection and 52 vaccinated with live measles vaccine from the L-16 strain. The study showed that both in the infectious disease and vaccinal process cell-mediated immunologic responses and changes in the specific humoral immunity are dissimilar. In measles disease they are manifested earlier and more marked than in the vaccinal process where even 30 days post-vaccination cell-mediated responses are not as manifest and frequent as in convalescents despite nearly similar levels of humoral immunity.