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The diagnostic value of enzyme immunoassay systems manufactured by different companies was comparatively studied to detect specific IgM antibodies to measles virus. The assay systems were shown to have a high sensitivity. The specificity was higher in the assay systems designed on the capture principle, a type of solid-phase enzyme immunoassay.

The test system developed at the Central Research Institute of Epidemiology, Ministry of Health of the Russian Federation for identification of hepatitis C virus RNA was studied. The sensitivity of the test system which the rate of similar results was 100% with its 5-fold reproduction was evaluated. That was 5 x 103 genomic equivalents (or international units) per ml of a sample. A scheme for evaluation of the reproductibility of test systems based on the polymerase chain reaction (PCR) by using model samples is proposed. Whether it can be used for intra- and extra-laboratory assessment of the quality of PCR analyses is discussed.

Results of comparative studies of tableted and epicutaneous live smallpox vaccines are presented. In experiments on rabbits by using histological, immunofluorescent, immunological and virological methods, higher safety and efficiency of the tableted vaccine than that of traditional smallpox epicutaneous vaccine were determined. The natural and physiological character of oral immunization was shown. The oral immunization was concluded to be a safe method of inoculation now and perspective for the use of recombinant vaccines based on vaccine virus in the absence of population immunity against smallpox.

The results of clinical trials of three types of candidate anti-AIDS vaccines are presented. Immunogenicity of different vaccine types and modern requirements to vaccines are analyzed. The advantages and disadvantages of protein, vector, and DNA vaccines and various protocols of vaccination are discussed and the advantages of the priming-booster immunization protocol are emphasized. Information about phase III clinical trials are presented. Tentative terms of introduction of vaccines into practice are presented.

HV monoclonal antibodies (MAb) were produced in order to improve the quality of HBsAg detection and their specific characteristics were compared with those of other MAbs. MAbs were characterized by asymmetric interactions with the antigen when used as first or second antibodies. The reactivity of a panel of HV and X MAb to ad and ay subtypes was studied by enzyme immunoassay. Mutual blocking (epitope mapping) of MAb helped select antibody couples for the creation of highly effective test system for the diagnosis of the major HBsAg subtypes. The sensitivity and specificity of MAbs were evaluated on reference and control panels of HBsAg sera and on serum specimens from a random sampling of 300 blood donors. The sensitivity of the most specific MAb pairs was 0.1 ng/ml for HBsAg subtype ay and 0.25 ng/ml for subtype ad. The specificity of attested MAb was 98.5% in incubation with stirring and 97% in static incubation. The optimal combinations of attested MAbs were used in the manufacture of Recomnathep B test system in the sandwich format.

Bubo-M, the first Russian combined vaccine, was found to have low reactogenicity. The difference between the number of postvaccinal reactions in the group of children immunized with Bubo-M (25.9%) and those in the group of children who had been simultaneously injected into different sites of the body with ADS-M toxoid (adsorbed DT toxoid with reduced antigen content) and hepatitis B vaccine (26.7%) was not statistically significant. Following immunization a considerable increase in the level of diphtheria and tetanus antibodies (p < 0.005) was observed in all children (100%), the level of HBs antibodies in the group of children immunized with Bubo-M (the geometric mean titer: 13,721 IU/l) essentially exceeding that observed in the control group injected with ADS-M toxoid and hepatitis B vaccine (the geometric mean of the titer: 2,441 IU/l). Bubo-M was duly registered and allowed for industrial production and medical use.

Bubo-M, the first Russian associated vaccine, was found to have low reactogenicity and high immunogenic potency. The frequency of postvaccinal reactions in the group of persons immunized with Bubo-M (20%) appeared to be considerably lower than among persons who received the combined injection of adsorbed DT toxoid with reduced antigen content and vaccine against hepatitis B (47.7%). Following the course of vaccination the level of anti-HBs considerably exceeded the protective level. Immune response to the diphtheria and tetanus components of Bubo-M exceeded that observed after immunization with absorbed DT toxoid with reduced antigen content (p < 0.05).

Morphological and immunofluorescent study of changes in the central nervous system of monkeys with mumps was carried out in order to determine the criteria of neurovirulence of different mumps virus strains. Quantitative evaluation showed a lower residual neurovirulence of L-3 strain vs. Jeryl Lynn and Urabe Am9 strains. Use of new methodological approaches to evaluation of mumps vaccine strain neurovirulence will improve the safety control of live mumps vaccines.

This paper sums up the results of controlled field clinical trials of adult and childhood variants of Harvix, inactivated vaccine from hepatitis A. The vaccine is weakly reactogenic and safe. After a single injection of Harvix-1440 vaccine to adults the percentage of seroconversions in previously seronegative individuals was 80.6%, with the mean geometrical antibody titer 119 mIU/ml. In children aged 3-10 years the percentage of seroconversions after a single injection of Harvix-720 vaccine was 100%, the mean geometrical of antibody titer being 427 mIU/ml. Results of laboratory control and field clinical trials recommend both variants of Harvix vaccine for prevention of hepatitis A in the Russian Federation.

A panel of anti-HCV sera (lot 03HC) was prepared from human sera obtained at blood transfusion centers and infectious hospitals. Donor sera and high-titer sera from patients infected with HCV were used. For positive samples, specific sera reactive with the core and/or NS proteins of HCV 1b and 2 were selected. Positive sera were standardized by the concentrations of IgG with a pool of negative sera containing no HBsAg and antibodies to HIV, HCV, and syphilis. The sera for the panel were selected and titered in screening and specific tests. The anti-HCV panel includes negative and positive sera with low and high titers. The panel sera are stabilized and can be stored for a short time at room temperature. The anti-HCV panel of sera, lot 02HC, was certified at L. A. Tarasevich Institute for Standardization and Control as anti-HCV reference panel intended for sensitivity, specificity, and stability control of diagnostic systems for detection of antibodies to HCV in Russia.

Vaccine "Grippol"--has been developed at the State Research Center--Institute of Immunology. The preparation belongs to new generation vaccines and is a trivalent polymer-subunit vaccine containing the sterile conjugate of influenza virus surface proteins, types A and B, bound with copolymer polyoxidonium. The administration of "Grippol" to children of school age (6-18 years) demonstrated low reactogenicity of the vaccine, its safety and sufficient prophylactic effectiveness. During observations on total morbidity (with the exception of influenza and acute respiratory diseases) no side effects produced by "Grippol" were registered. At the same time the fact that the morbidity rate of upper respiratory tract disease in the group of children immunized with the vaccine decreased in comparison with the control group (by 2.4 times) cannot be disregarded.

Controlled field clinical trials of Avaxim vaccine from hepatitis A (Pasteur-Merrier-Connot) were carried out in adults and children aged 3-14 years to evaluate its reactogenicity and antigenic properties. The vaccine was weakly reactogenic both in adults and children. A single injection of the vaccine resulted after 1 month in the production of anti-HAV antibodies in 77.4% initially seronegative adults and 94.5% children. In adults the mean geometrical titer of antibodies was 95 mIU/ml and in children 165 mIU/ml, which was 5-8 times higher than the protective titer. These data recommend Avaxim vaccine for practical public health.

Russian cultural concentrated inactivated vaccine protecting from hepatitis A--Hep-A-in-vac was used for immunization of children. The vaccine is slightly reactogenic and completely safe in children aged 3-17 years vaccinated twice in a dose of 0.25 ml. Double immunization of seronegative children with a 1-month interval led to conversion in 89.7% children. In 64.1% children titers of antibodies to hepatitis A virus reached 20 mIU/ml and higher, which indicates rather high antigenic activity of the vaccine.

Residual virulence of three vaccinia strains: Neurovaccine, L-IVP, and its recombinant Revacs-B expressing HBs and preS2 antigens of hepatitis B virus is compared. Insertion of HBs and preS2 antigens of hepatitis B virus in the genome of vaccinia virus strain L-IVP decreases its residual virulence and leads to a benign course of vaccinal reaction involving no deaths of rabbits, cotton rats, or guinea pigs. We may expect that recombinant vaccine Revacs B based on L-IVP strain will cause no postvaccinal complications under conditions of an appreciable decrease in population immunity to vaccinia virus.

A diagnostic kit for the determination of IgG antibodies to diphtheria toxin ("Abion", Germany) the use of analytical columns "Abicap" was studied in the specialized laboratory of the Tarasevich State Control Institute with a view to determine the possibility of its official registration in the Russian Federation. The kit was evaluated by the following criteria: the correspondence of the specified properties of the preparation to those actually observed; meeting the norms stated in the documents supplied with the kit and WHO requirements; the presence of advantages in comparison with the enzyme immunoassay. In the course of the trial positive results were obtained on all these points.

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.

The results of field clinical trials of Russian and American yeast vaccines against hepatitis B are presented. The study revealed that both vaccines were faintly reactogenic, safe and exhibited high immunological activity. After the full course of immunization following the schedule 0-1-2 months 92.5% and 97.5% of patients receiving, respectively. Russian vaccine "Combiotech" and American vaccine "H-B-Vax II" were found to have specific antibodies. The maximum effect was registered when the vaccines were introduced according to the schedule 0-1-6 months. Seroconversions were observed in 97.5% and 100% of the vaccinees receiving the Russian and American vaccines respectively, in the latter case the highest antibody level being observed. The use of the vaccines within the prophylactic immunization schedule showed that antibodies to hepatitis B appeared in immunized children in 93-100% of cases. Seroconversion indices and the levels of antibodies to diphtheria, tetanus, poliomyelitis and measles were statistically significant and were the same in children receiving only the vaccines according to the immunization schedule and in children immunized, in addition to these vaccines, against hepatitis B.

Presents the methods of oral and enteral administration of vaccines in tablets. Describes the method of oral administration with a sponge and the technique of administering large and small tablets in the intestinal tract. Describes the specific features of administering tablets to mice, guinea pigs, rabbits, and monkeys.

Experimental recombinant vaccine against hepatitis B Revacc B based on vaccinia virus has been tried. The preparation was weakly reactogenic but did not induce the production of anti-HBasAg antibodies. On the other hand, recombinant vaccine against hepatitis B Engerix B, used in a blind experiment as the agent of comparison, induced the production of anti-HBs in 91% of vaccinees.

The organizational and methodological separateness in the collection of pathogenic viruses impedes the development of universal approaches to practical collection. The authors propose a universal research program for the creation of specialized National Museums of Pathogens as reference and methodological centers within the framework of the Russian State Collection of Microorganisms. Further improvement of methods for virus collection is desirable.

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.

Comparative analysis of the specific activities of various batches of Hep-A-in-Vac vaccine showed that the immunologic efficacy of the agent directly depended on the content of hepatitis A virus antigen in the vaccine dose. The results of studying the immunogenicity of the agent on volunteers are compatible with the results of experimental studies and indicate that the test of guinea pigs adequately assesses this characteristic. Assessment of the immunogenic properties of Hep-A-in-Vac prepared using improved technology indicates that Russian vaccine injected three times in a dose containing at least 40 U EIA ensures 87.5% seroconversion in adult seronegative volunteers with the mean geometrical titer of antibodies to hepatitis A virus equal to 683 mIU/ml.

Clinical trials of inactivated hepatitis A vaccine Hep-A-in-Vac demonstrated its specific safety and moderate reactogenicity, manifesting by short-term fibrillar twitching of musculus deltoideus at the site of injection. After a course of three immunizations 87.5% seronegative vaccines developed a high level of specific antibodies to hepatitis A virus with at least 100 reverse values of titers. In controls antibody titers remained seronegative in 90% cases. These data indicate evident immunologic activity of Hep-A-in-Vac vaccine.

Controlled epidemiological studies were carried out to evaluate two recombinant vaccines against hepatitis B of Cuban and Belgian production by the parameters of reactogenicity, safety and antigenic activity. Two groups of adult subjects (n = 73 each) and two groups of children (n = 30 each) were selected among those free from hepatitis B markers carrier state. The adults were given both preparations in a dose of 20 micrograms at intervals of 0-1-4 months, and the children received 10 micrograms at 0-1-2 months. The comparative studies showed both vaccines to be poorly reactogenic, safe and inducing anti-Hns in 80-100% of triply vaccinated subjects in titres within 100-500 IU. No statistically significant differences in the examined parameters were found in the two preparations tested.

Five lots of peroxidase conjugates were studied in enzyme immunoassay systems "Recombinant-HIV" and "Peptoscreen-2" for detection of antibody to HIV. The conjugates differed from each other by the source of generation and methods of preparation. The conjugates were studied in biochemical tests and ELISA. When panels of sera from HIV-infected children and adults were employed, the advantages of using the anti-immunoglobulin conjugate over protein A-peroxidase conjugate were demonstrated, as the former increased the sensitivity of the test systems to HIV antibody detection.

Due to the features of its production technology, human leukocyte interferon (HLI) for intranasal administration is likely to contain ovalbumin (OA). Commercial batches of HLI were tested for the presence of OA responsible for the sensitizing effect of HLI given intranasally. The content of OA in commercial batches of HLI was shown to vary widely and to exceed by far the concentrations having the sensitizing effect. As a result of these studies, the upper limit of OA content was established and the technology of HLI production was modified. These measures permitted production of commercial batches of HLI with OA content not exceeding 0.05 micrograms/ml.

The changing epidemiological and distribution patterns of Japanese encephalitis in various southern and east Asian countries are described. Immunization is considered to be the only practical way to control the infection. Several vaccines have been developed and two types of inactivated vaccine are now available for use in man.