About the Results of Vaccination against COVID-19 for Employees of a Cheboksary Medical Organization

Relevance. In the 21st century, humanity is faced with a pandemic unprecedented in recent history, which brought with it huge losses. All the efforts of world science are aimed at ensuring that the new coronavirus infection becomes vaccine-controlled. The Ministry of Health of Russia included vaccination against COVID-19 in the national calendar of preventive vaccinations. The most vulnerable and significant in the epidemiological chain are representatives of socially active, intensively communicating professions, including medical workers.

Aims. The aim of the study was to assess the degree of severity of the post-vaccination immune response in employees of a medical organization vaccinated with the Gam-COVID-Vac preparation, who had not been ill and did not have antibodies before vaccination.

Materials & Methods. The post-vaccination immunity of 80 vaccinated employees was assessed 42–62 days after the start of vaccination and 6 months later; assessment of the safety of vaccination with the Gam-Kovid-Vak vector vaccine; selection of optimal screening tests for laboratory examination of persons before the planned vaccination. The results of the PCR test for the detection of SARS-CoV-2 RNA (at the post-vaccination stage four times with an interval of 7 days) and the determination of M and G immunoglobulins to SARS-CoV-2 by the ELISA method were analyzed, postvaccination complications and reactions were assessed at different stages, monitoring the state of health and assessing the dynamics of the post-vaccination immune response.

Results. A study conducted after 6 weeks showed the high immunological efficacy of the Gam-Covid-Vac vaccine; 100% of those vaccinated with one or two components of the vaccine had class G antibodies to SARS-CoV-2. Vaccination did not cause severe reactions during the observation period; among the side effects, general complaints and local pains at the injection site prevailed, which were of a short-term nature and did not have a significant impact on the health status and habitual rhythm of life of the participants. The resistance of those vaccinated to a new coronavirus infection decreased over time and amounted to 97.1% three months after vaccination and 95.6% after 6 months. COVID-19 disease in vaccinated employees (7.4% of cases of the number of vaccinated) was of moderate severity, did not lead to the development of pneumonia and respiratory failure, and did not require hospitalization.

Conclusions. The results obtained allow us to conclude that the effectiveness of vaccination against COVID-19 is quite high. Revaccination is well tolerated clinically and «amplifies» the immune response when exposed to SARS-CoV-2. Immunization of employees of medical organizations is necessary, because. this focus group is the most epidemiologically potentially dangerous in terms of the spread of infection.

1. Temporary guidelines. Prevention, diagnosis and treatment of novel coronavirus infection (covid-19). Version 13 (10/14/2021) of the Russian Ministry of Health. (In Russ). Available at: https://static-0.minzdrav.gov.ru/system/attachments/attaches/000/058/211/original/BMP-13.pdf [date of the application 06.06.2022]

2. Temporary guidelines. Prevention, diagnosis and treatment of novel coronavirus infection (covid-19). Version 13 (21.09.2021) of the Russian Ministry of Health, edited by E.G. Kamkin. (In Russ). Available at: https://static-0.minzdrav.gov.ru/system/attachments/attaches/000/058/075/original/ВМР_COVID-19_V12.pdf [date of the application 06.06.2022]

3. Instructions for the medical use of the drug Gam-Kovid-Vak. (In Russ). Available at: https://xn--80aesfpebagmfblc0a.xn--p1ai/info/ofdoc/who/ [date of the application 06.06.2022]

4. Instructions for use of a set of reagents for enzyme immunoassay detection of class G, M immunoglobulins to SARS-CoV-2, approved. 04/30/2020 Vector-Best JSC. International certificate ISO 13485. (In Russ). Available at: https://vector-best.ru/upload/iblock/0ab/0abfce055e809018ba9129604839c771.pdf [date of the application 06.06.2022]

5. Kuvshinova IN, Nekrasov BG, Levitskaya NI, et al. Sensitivity and specificity of reagent kits of Vector-Best JSC for the detection of immunoglobulins of different classes to SARSCoV-2. Directory of the head of the CDL. 2020;10:27–32 (In Russ).

6. Platonova TA, Golubkova AA, Sklyar MS, et al. On the issue of the effectiveness of vaccination of employees of medical organizations against COVID-19. Epidemiology and Vaccinal Prevention. 2022;21(1): 61–66 (In Russ). htpp://doi:10.31631/2073-3046-2022-21-1-61-66

7. Logunov DY, Dolzhikova IV, Shcheblyakov DV, et al. Gam-COVID-Vac VaccineTrial Group. Safety and efficacy of an rAd26 and rAd5 vector-based heterologous prime-boost COVID-19 vaccine: an interim analysis of a randomised controlled phase 3 trial in Russia. Lancet. 2021. Feb 20;397(10275):671–681. doi: 10.1016/S0140-6736(21)00234-8. Epub 2021 Feb 2. Erratum in: Lancet. 2021 Feb 20;397(10275):670. PMID: 33545094; PMCID: PMC7852454