50 research outputs found
Vaccination against Haemophilus influenzae type b in the Russian Federation and Abroad
No full textVaccination against Haemophilus influenzae type b infection is the principal method of its prophylaxis. This position is supported the results of extensive immunization which leading to significant morbidity decrease. The article discusses compositions of modern conjugated mono and associated vaccines, which has been licenced in Russia, USA, Great Britain, Canada and Australia, tactics and schedules of immunization. The special attention gives to immunocompromised person s vaccination, who possess the high sensibility to the infection
Theoretical and Experimental Substantiation of Alternative Methods for Quality Control of Live Anthrax Vaccine
No full textPreventive immunisation against anthrax is carried out in accordance with the national Immunisation Schedule for Epidemic Settings. The vaccination is performed using a live vaccine—a freeze-dried suspension of Bacillus anthracis STI-1 vaccine strain spores in a stabilizing media. Improvement of the quality control of immunobiological medicines is a pressing issue and an integral part of the quality management system. The aim of study was to streamline quality control of live anthrax vaccine in terms of the following test parameters: identification and specific activity (total spore concentration). Materials and methods: identification and specific activity (total spore concentration) tests were performed for samples of live anthrax vaccine, batch 266, produced by the 48 Central Scientific Research Institute. The identification test was performed using the B. anthracis immunochromatography test kit for express detection and identification of anthrax pathogen spores produced by the State Research Center for Applied Microbiology and Biotechnology (Obolensk). The specific activity (total spore concentration) was assessed by the visual method and calculated in the Goryaev chamber using the industry reference standard of bacterial suspension turbidity equivalent to 10 IU—OSO 42-28-85 (by the Scientific Centre for Expert Evaluation of Medicinal Products). The number of live spores in live anthrax vaccine was determined by the microbiological method (by inoculating media). The statistical processing of the results was performed using Excel and Statistica 10.0. Results: the authors provided theoretical and experimental substantiation to support the feasibility of using immunochromatography as an alternative identification test method for live anthrax vaccine. Test samples dilutions of 108 microbial cells per millilitre and 109 microbial cells per millilitre are used in the test. The authors developed a test procedure for determination of the total spore concentration (specific activity) in live anthrax vaccine using an industry reference standard of turbidity equivalent to 10 IU, and proposed a formula for calculation of the total spore concentration. Conclusions: the developed test procedures could be recommended for inclusion in the live anthrax vaccine specification files as alternative methods of quality control
Comparative analysis of the results of live anthrax vaccine identification by immunofluorescence and immunochromatography
No full textINTRODUCTION. The quality evaluation of live anthrax vaccines will benefit from the implementation of alternative testing methods that are capable of specific identification of the Bacillus anthracis spore antigen using the appropriate diagnostic products that are authorised in the Russian Federation for the detection of B. anthracis spores.AIM. This study aimed to investigate the applicability of immunofluorescence analysis to the identification of live anthrax vaccines and compare this method with immunochromatography.MATERIALS AND METHODS. The study used commercial batches of a live anthrax vaccine and Russian diagnostic products, including diagnostic dry adsorbed fluorescent anti-anthrax spore immunoglobulins and an immunochromatographic assay (ICA) reagent kit for rapid detection and identification of B. anthracis spores (ICA system for B. anthracis). For smears and ICA system reactions, the authors prepared working solutions of bacterial suspensions at spore concentrations typical of the B. anthracis STI-1 vaccine strain. The spore concentrations were achieved using the pharmacopoeial reference standard (RS) for the opacity of bacterial suspensions of 10 international units (IU). Identification reactions involved the registration of immune complex formation.RESULTS. Immunofluorescence tests of the live anthrax vaccine demonstrated bright greenish-yellow envelope fluorescence with an intensity score of 3+ to 4+ for smears stained with diagnostic immunoglobulins at 1:32 and 1:64 dilutions. Immunochromatographic tests of the live anthrax vaccine detected the spore antigen at vaccine concentrations of 109 and 108 spores/mL, with the test strips showing two distinct dark-pink lines indicative of immunoprecipitation. According to the results obtained using the selected methods, the tested microbial culture was confirmed as B. anthracis.CONCLUSIONS. Immunochromatography and immunofluorescence tests with appropriate diagnostic preparations are convenient and reliable tools for the species-specific detection of B. anthracis STI-1 spores in the live anthrax vaccine. The results obtained in the anthrax vaccine identification tests provide a basis for recommending the above methods as supplementary alternatives to Ziehl–Neelsen bacteriological staining, which is currently prescribed by the State Pharmacopoeia of the Russian Federation
Application of alternative identification methods for live tularaemia and brucellosis vaccines
No full textSCIENTIFIC RELEVANCE. The sanctions currently imposed on the Russian Federation requireusing Russian diagnostic products in vaccine quality assessments, as well as searching for alternative testing methods, in particular, serological ones.AIM. This study aimed to demonstrate the possibility of using alternative serological methods, including immunoenzymatic, direct agglutination, and indirect haemagglutination methods, for the identification of tularaemia and brucellosis vaccines in studies and quality assessments.MATERIALS AND METHODS. This study used the established pharmacopoeial reference standard (RS) for the bacterial suspension opacity of 10 international opacity units, the established pharmacopoeial RS for and two commercial batches of the live brucellosis vaccine (Brucella abortus 19 BA), and the established and candidate pharmacopoeial RSs for the live tularaemia vaccine (Francisella tularensis 15 NIIEG). These pharmacopoeial RSs were certified by the Scientific Centre for Expert Evaluation of Medicinal Products. Serological testing used Russian commercial diagnostic products, including dry diagnostic sera (polyvalent brucellosis and tularaemia sera for agglutination tests), a liquid erythrocytic diagnostic preparation of tularaemia immunoglobulin, and enzyme immunoassay (ELISA) diagnostic kits for detecting the causative agents for brucellosis and tularaemia. Statistical analysis involved using Microsoft Excel (P=0.95) for ELISA results and qualitative evaluation for the results of direct agglutination and indirect haemagglutination tests.RESULTS. All the tested batches demonstrated positive results. Live brucellosis vaccine batches showed positive results in the slide agglutination tests, while live tularaemia vaccine batches yielded positive results in the tube agglutination tests. All indirect haemagglutination tests showed haemagglutination in live tularaemia vaccine samples at the same concentration as positive control samples (6.25×10⁶ cells/mL). ELISA tests showed similar optical density values (D) for the two vaccines and positive control samples. Live tularaemia and brucellosis vaccines (undiluted, 1.0×10⁹ cells/mL) had D=2.133±0.273 and D=0.127±0.013, whereas the corresponding control samples had D=1.942±0.056 and D=0.123±0.007, respectively. The results reflected the presence of brucellosis or tularaemia microbes in the samples, confirming the identity of the vaccines.CONCLUSIONS. Serological immunoenzymatic, direct agglutination, and indirect haemagglu tination methods with Russian diagnostic products can be used to identify live brucellosis and tularaemia vaccines during quality assessment. The agglutination method with Russian diagnostic sera can be recommended as an alternative quality assessment method for the identification of live brucellosis and tularaemia vaccines, as this method offers time efficiency, simple visual evaluation of results, and low costs and relatively long shelf lives of diagnostic products. However, ELISA and indirect haemagglutination methods cannot be recommended for this purpose because of their labour-intensive and uneconomical nature. The results of this study may support the introduction of the agglutination method in the regulatory documents for live brucellosis and tularaemia vaccines (as an alternative method)
Prospects for Improving Quality Evaluation of the Live Brucellosis Vaccine in Terms of Specific Activity
No full textProphylactic immunisation against brucellosis is part of the National Immunisation Schedule for Epidemic Settings. The immunisation is performed with a live vaccine—a lyophilized suspension of the Brucella abortus strain 19 BА in a stabilizing medium. The paper presents the results of quality evaluation of 9 batches of live brucellosis vaccine that were submitted to the Testing Centre for Evaluation of Medicinal Immunobiological Products’ Quality of the Federal State Budgetary Institution “Scientific Centre for Expert Evaluation of Medicinal Products” of the Ministry of Health of the Russian Federation for assessment of the product’s compliance with the established specifications. The paper also presents the results of evaluation of the passport information provided by the manufacturer for these batches. There is no doubt about the need for objective quality evaluation of brucellosis vaccines as well as about the significance of its improvement.The aim of study was to assess the prospects for improving quality evaluation of live brucellosis vaccines in terms of Specific activity (concentration of microbial cells, number of living microbial cells, number of cutaneous doses).Materials and methods: specific activity (concentration of microbial cells and number of living microbial cells) was determined by visual and microbiological methods using the industrial reference standard of brucellosis vaccine OSO 42-28-396-2018, batch 6 and the bacterial suspension of the Brucella abortus strain 19 BА acquired from the joint stock company Scientific and Production Association “Microgen” in 2016. The number of cutaneous doses in the brusellosis vaccine was determined by the calculation method. Statistical processing of the results was performed using Microsoft Excel.Results: there was a mismatch between the brucella concentration coefficient of 1.7×109 microbial cells/mL determined by comparison with the industrial reference standard of bacterial suspension turbidity, 10 IU and the actual concentration of microbial cells obtained in the study. According to preliminary results, the brucella concentration coefficient corresponding to the industrial reference standard of bacterial suspension turbidity, 10 IU can reach 3.0×109 microbial cells/mL.Conclusions: the obtained results can serve as a basis for amending the data on the brucella concentration coefficient in the Passport and the Instructions for use of the industrial reference standard of bacterial suspension turbidity, 10 IU, as well as the Specific activity section (concentration of microbial cells, number of living microbial cells, number of cutaneous doses) of the established specifications for the brucellosis vaccine. Before amending the information on the brucella concentration corresponding to 10 IU in the Passport and the Instructions for use of the reference standard of bacterial suspension turbidity (OSO 42-28-85P), additional studies should be performed with other types of brucella
Evaluation of the applicability of immunochromatography to the identification of live plague vaccines and the tularaemia allergen (Tularin)
No full textThe regulatory standards require that the identification of live plague vaccines and the liquid tularaemia allergen (Tularin) should be performed by immunofluorescence. A major drawback of the recommended method is its labour intensive nature. However, immunochromatography represents an alternative method that offers a number of advantages, including rapid testing and easy result interpretation. The aim of the study was to assess the applicability of immunochromatography to the identification of live plague vaccines and the liquid tularaemia allergen (Tularin).Materials and methods. The authors performed identification tests using samples of the pharmacopoeia standard for live plague vaccines, three commercial batches of a live plague vaccine, and two batches of the liquid tularaemia allergen (Tularin). These samples were tested using immunochromatographic assay (ICA) reagent kits for rapid detection and identification of Yersinia pestis (ICA System for Y. pestis) and Francisella tularensis (ICA System for F. tularensis) manufactured by the State Scientific Center for Applied Microbiology and Biotechnology.Results. The findings show that immunochromatography is an effective, rapid, and species-specific method to confirm the presence of Y. pestis in a sample of a live plague vaccine or F. tularensis in a sample of the liquid tularaemia allergen (Tularin). To perform identification tests by immunochromatography, the authors recommend diluting live plague vaccine samples to a concentration of 109 bacterial cells/mL and using undiluted samples of the liquid tularaemia allergen (Tularin).Conclusions. The study results may support the inclusion of ICA into the regulatory standards for live plague vaccines and the liquid tularaemia allergen (Tularin) as an alternative identification method
<i>Haemophilus</i><i> influenzae</i> type <i>b</i>. Incidence rate and preventive vaccination
No full textThe article summarizes the existing knowledge on the infection caused by Haemophilus influenzaetypeb (Hib-infection). It examines clinical immunology aspects of vaccination against Hib-infection. The authors cite data on the incidence of invasive Hib-infections in the Russia and other countries. Special attention is given to preventive vaccination against Hib-infection. The article describes properties of polysaccharide and conjugate vaccines against Hib-infection and examines different immunization schedules, therapeutic indications and contraindications, potential adverse reactions, and the vaccination procedure
Meningococcal disease. Polysaccharide meningococcal vaccines. The historical aspects and the current state of vaccine development. Report 2
No full textThe present article describes clinical signs of meningococcal disease. It justifies the necessity of its vaccine prevention. The article provides with the historical data on the evolution of inoculants from corpuscular inactivated vaccines to modern chemical polyvalent vaccines. It provides a glimpse of the efficacy of the use of corpuscular vaccines and considers the corresponding implications. The historical overview includes the use of mono-, di-, tetravalent polysaccharide vaccines, and the discussion on the role of bactericidal antibodies in the formation of immunity against meningococcal disease. The article also describes the experience of using polysaccharide vaccines in various countries and in different age groups in randomized clinical trials. It provides with the data analysis about the effect of vaccination on the level of meningococcal carriage and the incidence of meningococcal disease. The WHO’s position on the use of polysaccharide meningococcal vaccines in routine practice are also provided. In the conclusion the article presents the prospects for further use of polysaccharide vaccines to control the spread of meningococcal disease
Using Shewhart charts to monitor quality characteristics of preventive vaccines for tuberculosis
No full textScientific relevance. The quality of medicinal products, particularly vaccines, is contingent on the stability of the manufacturing process at all stages, which can be evaluated using Shewhart charts for data obtained by monitoring the quality attributes of interest.Aim. This study evaluated the stability of the quality and manufacturing processes of the BCG and BCG-M tuberculosis vaccines using Shewhart charts.Materials and methods. This study focused on samples of the BCG tuberculosis vaccine and the BCG-M tuberculosis vaccine, a less reactogenic alternative for primary immunisation. Both vaccines were released to the market in 2019–2022. The quality of samples was assessed for stability based on their potency and total bacterial count, which are the key parameters for immunogenicity evaluation. These quality parameters were compared using test results submitted by the manufacturer and obtained at the testing centre. The authors plotted individuals charts (X-charts) and moving range charts (R-charts) in accordance with national standards GOST R 50779.42-99 and GOST R ISO 7870-2-2015.Results. The quality of the BCG and BCG-M vaccines remained stable during the entire follow-up period (2019–2022). For some periods, the retrospective analysis of R- and X-charts revealed characteristic trends meeting special cause criteria. The Pearson correlation coefficient (r) between the data submitted by the manufacturer and the data obtained at the testing centre ranged from 0.2 to 0.8.Conclusions. The Shewhart charts demonstrated that the quality parameters of the BCG and BCG-M tuberculosis vaccines tested in 2019–2022 were stable. These vaccines had stable manufacturing processes, as shown by the R- and X-charts. However, the warning signs indicated that additional measures should be taken to standardise the manufacturing processes. The findings suggest that Shewhart charts may be recommended for monitoring the production and quality of tuberculosis vaccines
Meningococcal disease. Meningococcal conjugate polysaccharide vaccines and new generation vaccines. Report 3
No full textDespite the progress in fighting against infectious diseases of bacterial origin, the incidence of generalized forms of meningococcal infection (GFMI) remains a topical public health problem not only in countries with historical high incidence, but also in countries considered to be relatively «secured» in regard to the mentioned infection. In the 60s of the last century the production of high-polymer forms of meningococcal polysaccharides was started. These high molecular weight polysaccharides were used for the development of vaccines. They helped to significantly reduce the incidence of GFMI in certain countries, including the countries of the so-called African «meningitis belt». Unfortunately, polysaccharide vaccines have well-known deficiencies, prompting the researchers to develop advanced conjugate vaccines. Current new generation of vaccines are based on conjugates of polysaccharides of different serogroups with carrier proteins such as tetanus toxoid, a modified diphtheria toxin (CRM197) or outer membrane proteins. Mono- and multivalent conjugate vaccines were developed and tested. Conjugate vaccines have several advantages compared to the polysaccharide vaccines. They stimulate the formation of immunological memory, and therefore are able to provide consistent protection against meningococcal disease in children of an early age group. In particular, monovalent conjugate vaccine against serogroup C meningococcal disease were proven to be very effective. This vaccine was successfully used in the UK. There are also tetravalent conjugate vaccines Menactra and Menveo. These preparations consist of serotype A, C, W135 and Y meningococcal polysaccharide conjugates. These polysaccharides stimulated the production of bactericidal antibodies in 90% of immunized individuals. Certain success was also achieved in developing genetically engineered vaccines and the vaccines based in meningococcal outer membrane vesicles (OMV-vaccines). OMV-vaccines showed to be effective in the fight against epidemics of meningitis caused by serogroup B meningococcus. Polysaccharide vaccines against serogroup B meningococcus in different designs proved to be ineffective because of their low immunogenicity. There are certain difficulties in developing an ultimate vaccine that protects against GFMI, due to the fact that there is a variety of antigenic types of serogroup B meningococcus. So far the scientists only have managed to develop a strain-specific vaccine suitable for fighting GFMI outbreaks, caused by the specific strain of serogroup B meningococcus. The opportunities to enhance the efficacy of vaccines against serogroup B meningococcus are still being discussed
