Prognostic criteria for the development of severe clinical forms of COVID-19 in medical organization workers

Employees of medical organizations are one of the risk groups for infection with a new coronavirus infection (COVID-19), including with the development of severe clinical forms. The aim of the study was to analyze the clinical manifestations of a new coronavirus infection in medical workers with the determination of laboratory markers for the development of severe COVID-19. Material and methods. The study included 186 medical workers who had COVID-19 in 2020. In 67 people (observation group), the disease occurred in the form of pneumonia, in 119 people (comparison group) - acute respiratory infection caused by SARS-CoV-2. In the acute period of the disease, a laboratory examination was carried out: a general clinical blood test, CD-typing of lymphocyte subpopulations, assessment of biochemical parameters, determination of parameters of the hemostasis system and cytokine levels. Using the binary logistic regression method, we have built multifactor models. To determine the threshold values of the indicators, we used ROC analysis. Statistical processing of materials was carried out using Microsoft Office 2016 and IBM SPSS Statistics (version 26). The differences were considered statistically significant at p<0.05. Results and discussion. The most frequent clinical manifestations of COVID-19 were: weakness, fever, myalgia, arthralgia, difficulty in nasal breathing, serous-mucous discharge from the nose, sore throat, cough, feeling of "tightness" in the chest, shortness of breath, headache, pain in the eyeballs, dizziness, anosmia, ageusia and dyspeptic manifestations in the form of diarrhea, nausea or vomiting. Markers associated with the development of severe pneumonia associated with COVID-19 have been identified. Threshold values of laboratory parameters for predicting the severe course of COVID-19 were determined: the number of platelets (less than 239x109/l), lymphocytes (less than 1.955x109/l), cytotoxic T-lymphocytes (less than 0.455x109/l), T-helper cells (less than 0.855x109/l), NK-cells (less than 0.205x109/l), ESR (more than 11.5 mm/h), LDH (more than 196 units/l), total protein (less than 71.55 g/l), D-dimer (more than 0.325 mcg/ml), CRP (more than 4.17 mg/l), IL-6 (more than 3.63 pg/l). Conclusion. The data obtained make it possible to predict the possibility of developing a severe variant of the COVID-19 course.Copyright © 2022 Infectious Diseases: News, Opinions, Training. All rights reserved.

Assessment of specific T-cell immunity in patients who have been ill and vaccinated against COVID-19.

Introduction. In the context of a pandemic of a new coronavirus infection (COVID-19), research on the peculiarities of the formation of an immune response to SARS-CoV-2 in patients who have been ill and vaccinated is of particular relevance. However, most studies are currently devoted to evaluating only the humoral link of immunity, and its cellular component remains insufficiently studied. The aim of the study was to evaluate the features of the formation and changes of the T-cell link of immunity in patients with a new coronavirus infection and vaccinated against this disease. Materials and methods. The study was performed on the basis of the clinical and diagnostic laboratory of the European Medical Center "UMMC-Health "LLC. Specific T-cell immunity was evaluated using ELISPOT technology. In the course of the study, 72 blood samples of employees of medical organizations were analyzed, including 26 from those who had a new coronavirus infection, 23 from persons who were intact according to COVID-19 before vaccination and 23 from the same employees after vaccination (<<Gam-Covid-Vac>>). In addition, each of the study participants was examined to determine specific class G antibodies (IgG) by solid-phase enzyme immunoassay using SARS-CoV-2-IgG-ELISA-BEST test systems (manufactured by VECTOR-BEST JSC). Results and discussion. In the group of patients (26 people), T-lymphocytes capable of specifically reacting to SARSCoV-2 antigens were detected in 100% of cases, even in individuals with IgG elimination. It should be noted that the response was more pronounced when meeting with M-and N-pepdids, compared with S-protein. 22 out of 23 COVID-19 intact individuals had no T-cell immunity to coronavirus infection before vaccination, but one employee had a response to 3 proteins-M, N, S, which indicates that he had previously encountered the SARS-CoV-2 virus. After vaccination with the drug "Gam-Covid-Vac", 22 (95.6%) employees revealed a T-cell response, while 21-only to S-protein, and an employee with a previously detected immune response-after vaccination, the response to M -, N-proteins remained almost at the same level, and the cellular response to S-peptide doubled. Conclusion. Thus, based on the results of the study, important materials were obtained on the peculiarities of the formation of a specific T-cell immune response to a new coronavirus infection. The obtained data provide a broader understanding of the immune response in new coronavirus infection in patients who have been ill and vaccinated and can be used in the future when planning preventive and anti-epidemic measures.Copyright © 2022 Interregional public organization Association of infectious disease specialists of Saint-Petersburg and Leningrad region (IPO AIDSSPbR). All rights reserved.

Assessment of specific T-cell immunity in patients who have been ill and vaccinated against COVID-19.

Introduction. In the context of a pandemic of a new coronavirus infection (COVID-19), research on the peculiarities of the formation of an immune response to SARS-CoV-2 in patients who have been ill and vaccinated is of particular relevance. However, most studies are currently devoted to evaluating only the humoral link of immunity, and its cellular component remains insufficiently studied. The aim of the study was to evaluate the features of the formation and changes of the T-cell link of immunity in patients with a new coronavirus infection and vaccinated against this disease. Materials and methods. The study was performed on the basis of the clinical and diagnostic laboratory of the European Medical Center "UMMC-Health "LLC. Specific T-cell immunity was evaluated using ELISPOT technology. In the course of the study, 72 blood samples of employees of medical organizations were analyzed, including 26 from those who had a new coronavirus infection, 23 from persons who were intact according to COVID-19 before vaccination and 23 from the same employees after vaccination (<<Gam-Covid-Vac>>). In addition, each of the study participants was examined to determine specific class G antibodies (IgG) by solid-phase enzyme immunoassay using SARS-CoV-2-IgG-ELISA-BEST test systems (manufactured by VECTOR-BEST JSC). Results and discussion. In the group of patients (26 people), T-lymphocytes capable of specifically reacting to SARSCoV-2 antigens were detected in 100% of cases, even in individuals with IgG elimination. It should be noted that the response was more pronounced when meeting with M-and N-pepdids, compared with S-protein. 22 out of 23 COVID-19 intact individuals had no T-cell immunity to coronavirus infection before vaccination, but one employee had a response to 3 proteins-M, N, S, which indicates that he had previously encountered the SARS-CoV-2 virus. After vaccination with the drug "Gam-Covid-Vac", 22 (95.6%) employees revealed a T-cell response, while 21-only to S-protein, and an employee with a previously detected immune response-after vaccination, the response to M -, N-proteins remained almost at the same level, and the cellular response to S-peptide doubled. Conclusion. Thus, based on the results of the study, important materials were obtained on the peculiarities of the formation of a specific T-cell immune response to a new coronavirus infection. The obtained data provide a broader understanding of the immune response in new coronavirus infection in patients who have been ill and vaccinated and can be used in the future when planning preventive and anti-epidemic measures.Copyright © 2022 Interregional public organization Association of infectious disease specialists of Saint-Petersburg and Leningrad region (IPO AIDSSPbR). All rights reserved.

On the Issue of Evaluating the Effectiveness of Vaccination of Employees of Medical Organizations against COVID-19

Relevance. Active mass vaccination of the population against a new COVID-19 is being carried out on the territory of the Russian Federation, which is recognized as a priority strategy for the country's healthcare for the near and long-term periods. One of the main risk groups that are subject to priority vaccination is medical workers. Aims. To evaluate the effectiveness of vaccination of medical organizations ' employees against COVID-19 based on the results of a 6-month prospective follow-up. Materials and methods. The observation group consisted of 356 employees of a medical organization who were vaccinated against COVID-19 with the drug «Gam-Covid-Vac» from December 2020 to April 2021. The effectiveness of vaccination of employees was evaluated by the coefficient of IgG positivity to SARS-CoV-2 by solid-phase enzyme immunoassay 3 weeks after the first administration and 3–4 weeks after the second administration of the vaccine and then 1 time per month. Employees who were revaccinated after 5–6 months. After the initial vaccination, they were examined 10–14 days after the introduction of the first component «Gam-CovidVac». A total of 1921 serum samples were studied. A specific T-cell immune response was determined in two study participants without seroprotection after administration of two components of the «Gam-Covid-Vac» vaccine and eight employees with the elimination of IgG antibodies 4–5 months after vaccination using ELISPOT technology. In addition, 92 blood serum samples of 32 employees from the observation group were examined for specific antibodies to adenovirus by indirect enzyme immunoassay. From December 2020 to June 2021, the study participants were subjected to dynamic clinical observation, once a week they were examined by PCR to detect SARS-CoV-2 RNA in smears from the pharynx and nose (a total of 5696 samples). Results. After the completed course of immunization, the formation of both a humoral (in 99.4% of cases) and cellular immune response (100% among the studied samples) was confirmed. In the next 6 months after vaccination, cases of coronavirus infection were registered in 4.8% of those vaccinated, including 1 person – in the first month after vaccination and 16 – 3–5 months after vaccination. In all cases, the disease occurred in the form of an acute respiratory infection of mild or moderate severity and was characterized by a shorter period of virus isolation compared to similar data on the persistence of the virus in unvaccinated patients (15 days in vaccinated compared to 22 days in unvaccinated). It was found that the presence of immunity to adenovirus infection during vaccination with the drug «Gam-Covid-Vac» did not affect the possibility of forming an immune response to COVID-19. In the group of persons re-vaccinated with the first component of «Gam-Covid-Vac» after 5–6 months. after the initial vaccination, an immune response was received during the follow-up period. Conclusion. Thus, according to the results of the study, a high immunological and epidemiological effectiveness of vaccination against COVID-19 with the drug «Gam-Covid-Vac» was established in a group of medical workers, and the effectiveness and safety of the administration of a booster dose of the vaccine after primary vaccination was also shown. Keywords: coronavirus infection, COVID-19, vaccination, «Gam-Covid-Vac», medical workers, humoral and cellular immune response No conflict of interest to declare. © 2022, Numikom. All rights reserved.