Abstract:IgM and IgG antibodies to the SARS-CoV-2 virus are detected in subjects who have recovered from COVID-19; IgM antibodies persist in a 1/3 of infected subjects up to 12 months from the moment of the disease, while IgG antibodies are present in the vast majority of cases (97%; medium and high levels antibodies were registered in 85% of cases). By the 12th month, 40% of those who recovered still have a very high level of IgG antibodies to the S-protein (>500 BAU/ml). In the feces, urine, and blood serum of patien… Show more
Relevance. On the territory of the Russian Federation, mass vaccination of the population is recognized as a priority health strategy against COVID-19, Gam-COVID-Vac vaccine has been widely used. The main risk group, which is subject to priority vaccination, are employees of medical organizations (MO). The determination of IgG to SARS-CoV-2 is an important parameter for assessing the intensity and duration of post-vaccination immunityAims. Study the immunological efficacy of the vaccine Gam-COVID-Vac used by employees of a psychiatric hospital and a regional hospital.Materials and methods. A study of the blood sera of 410 employees of two MO of various profiles who received one full course of the Gam-COVID-Vac» vaccine for the presence of IgG to RBD Spike SARS-CoV-2 using a set of reagents «SARS-CoV-2-IgG quantitative-ELISA-BEST» and IgG to NC SARS-CoV-2 using a set of reagents «ELISA anti-SARS-CoV-2 IgG».Results and discussion. Specific IgG to RBD Spike SARS-CoV-2 after vaccination with «Gam-COVIDVac » were found in 92.9% of psychiatric hospital staff and 98.0% of the regional hospital. Antibodies of class G to SARS-CoV-2 with a level of 300 BAU/ml or more were detected in 11.6% of psychiatric hospital staff and in 70.0% of regional hospitals, which is associated with the smallest proportion of persons in a psychiatric hospital with hybrid immunity than in a regional hospital (67.4% vs. 89.0%, respectively). A study of employees of the Ministry of Defense of various profiles revealed a difference in the level of IgG to RBD Spike SARS-CoV-2: 178.0 BAU/ml in a psychiatric hospital and 366.0 BAU/ml in a regional hospital. In a psychiatric hospital, the IgG level was highest up to 3 months after the completed vaccination – 166.4 BAU/ml, in a regional hospital from 3 to 6 months – 362.8 BAU/ml, then the number of antibodies decreases, which indicates the importance of monitoring for class G antibodies to SARS-CoV-2 at different times after vaccinations. Among the employees of the two MO, mild forms of the COVID-19 disease prevailed.Conclusion. Thus, the high immunological effectiveness of vaccination against COVID-19 with Gam-COVID-Vac was established in a group of employees of two MO, and the need for serological monitoring for the purpose of revaccination was also shown.
Relevance. On the territory of the Russian Federation, mass vaccination of the population is recognized as a priority health strategy against COVID-19, Gam-COVID-Vac vaccine has been widely used. The main risk group, which is subject to priority vaccination, are employees of medical organizations (MO). The determination of IgG to SARS-CoV-2 is an important parameter for assessing the intensity and duration of post-vaccination immunityAims. Study the immunological efficacy of the vaccine Gam-COVID-Vac used by employees of a psychiatric hospital and a regional hospital.Materials and methods. A study of the blood sera of 410 employees of two MO of various profiles who received one full course of the Gam-COVID-Vac» vaccine for the presence of IgG to RBD Spike SARS-CoV-2 using a set of reagents «SARS-CoV-2-IgG quantitative-ELISA-BEST» and IgG to NC SARS-CoV-2 using a set of reagents «ELISA anti-SARS-CoV-2 IgG».Results and discussion. Specific IgG to RBD Spike SARS-CoV-2 after vaccination with «Gam-COVIDVac » were found in 92.9% of psychiatric hospital staff and 98.0% of the regional hospital. Antibodies of class G to SARS-CoV-2 with a level of 300 BAU/ml or more were detected in 11.6% of psychiatric hospital staff and in 70.0% of regional hospitals, which is associated with the smallest proportion of persons in a psychiatric hospital with hybrid immunity than in a regional hospital (67.4% vs. 89.0%, respectively). A study of employees of the Ministry of Defense of various profiles revealed a difference in the level of IgG to RBD Spike SARS-CoV-2: 178.0 BAU/ml in a psychiatric hospital and 366.0 BAU/ml in a regional hospital. In a psychiatric hospital, the IgG level was highest up to 3 months after the completed vaccination – 166.4 BAU/ml, in a regional hospital from 3 to 6 months – 362.8 BAU/ml, then the number of antibodies decreases, which indicates the importance of monitoring for class G antibodies to SARS-CoV-2 at different times after vaccinations. Among the employees of the two MO, mild forms of the COVID-19 disease prevailed.Conclusion. Thus, the high immunological effectiveness of vaccination against COVID-19 with Gam-COVID-Vac was established in a group of employees of two MO, and the need for serological monitoring for the purpose of revaccination was also shown.
Vaccination against COVID-19 has occurred in Russia for more than two years. According to the Russian official clinical guidelines to maintain tense immunity in the conditions of the ongoing COVID-19 pandemic, it is necessary to use booster immunization six months after primary vaccination or a previous COVID-19 contraction. It is especially important to ensure the maintenance of protective immunity in the elderly, who are at risk of severe courses of COVID-19. Meanwhile, the immunological effectiveness of the booster doses has not been sufficiently substantiated. To investigate the immunogenicity of Sputnik V within the recommended revaccination regimen and evaluate the effectiveness of booster doses, we conducted this study on 3983 samples obtained from individuals previously vaccinated with Sputnik V in Moscow. We analyzed the level of antibodies in BAU/mL three times: (i) six months after primary immunization immediately before the booster (RV), (ii) 3 weeks after the introduction of the first component of the booster (RV1), and (iii) 3 weeks after the introduction of the second component of the booster (RV2). Six months after the primary vaccination with Sputnik V, 95.5% of patients maintained a positive level of IgG antibodies to the receptor-binding domain (RBD) of SARS-CoV-2. The degree of increase in the specific virus-neutralizing antibodies level after revaccination increased with a decrease in their initial level just before the booster dose application. In the group of people with the level of antibodies up to 100 BAU/mL six months after the vaccination, a more than eightfold increase (p < 0.001, Wilcoxon criterion with Bonferroni adjustment) in the level of specific antibodies was observed (Me = 8.84 (IQR: 3.63–30.61)). A significant increase in the IgG level after receiving both the first and the second booster doses occurred at the initial titer level up to 300 BAU/ mL (p < 0.001) in those who did not contract COVID-19 in the past and up to 100 BAU/mL (p < 0.001) in those who were previously infected with SARS-CoV-2. A significant increase in the antibody level after the first dose of the booster was noted for people who had up to 500 BAU/mL (p < 0.05), regardless of the previous COVID-19 infection. Thus, revaccination is most effective in individuals with an antibody level below 500 BAU/mL, regardless of the vaccinee age and COVID-19 contraction. For the first time, it has been shown that a single booster dose of the Sputnik vaccine is sufficient to form a protective immunity in most vaccinees regardless of age and preexisting antibody level.
Background. Constant assessment of the dynamics of the main characteristics of the epidemic process is the basic function of epidemiological surveillance of infectious diseases. The search for factors that determine changes in the characteristics of the epidemic process makes it possible to develop timely management decisions and reduce the risk of an increase in the scale of the pandemic. Moscow is the main centre of attraction for the population of other Russian regions with the most complex structure of social links and the highest population density.
The purpose of the study is to identify factors that potentially determine the trends of observed changes using a molecular epidemiological analysis of the main characteristics of the epidemic process of a new coronavirus infection (COVID-19).
Materials and methods. For the analysis, the data of Russian national genome sequence database of SARS-CoV-2 virus (VGARus) were combined with information on morbidity and mortality presented at the official internet resources стопкоронавирус.рф and Yandex DataLens, the dynamics of vaccination, COVID-19 disease incidence and hospitalization from the portal Gogov.ru. A multicentre retrospective observational epidemiological study was conducted to examine the sex and age structure of hospitalised patients. Anonymized case histories of patients with COVID-19 collected at different follow-up periods in the institutions of Moscow (41,561 cases) served as a source of data for the sex and age structure analysis.
Results. We identified 11 periods with significantly different complex epidemiological characteristics. A decrease in the incidence among young people of working age during the period of restrictive measures was revealed. In 3 out of 11 worsening of the epidemic situation coincided with the beginning of the circulation of a new genetic variant of the pathogen COVID-19 (variants Wuhan, Delta, Omicron). A decrease in the incidence in the summer period was noted, regardless of the circulating genetic variants.
Conclusion. A significant part of the observed dynamics of the characteristics of the epidemic process in Moscow can be explained by the properties of the pathogen, seasonality and dynamics of magnitude of the herd immunity. The influence of the dynamics of the herd immunity indicators on the course of the epidemic process is to be studied further.
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