Frequency of SARS-CoV-2 infection in hemodialysis patients

Patients with end-stage chronic kidney disease treated with hemodialysis are at risk of infection and severe course of the new coronavirus infection. This opinion was based on the data obtained as a result of PCR testing during the active phase of the disease with detailed clinical symptoms. However, this diagnostic method does not allow one to fully assess the prevalence of infection in the population. The aim - studying of the frequency of SARS-CoV-2 infection in patients receiving hemodialysis treatment and the spectrum of antiviral antibodies, depending on the nature of the course of COVID-19. Material and methods. 100 patients with chronic kidney disease (stage 5D) treated at the outpatient Dialysis Center (MCVTP) were included in the study by a simple random sample. The assessment of SARS-CoV-2 infection was carried out by analyzing the material of smears obtained from the naso-oropharynx by PCR and blood serum samples by ELISA. The study excluded 14 patients with dubious results for the determination of serological markers SARS-CoV-2 and 1 patient with active infection, who was isolated from the RNA of the virus. Results. IgM and IgG antibodies were detected in 49 (57.6%) of the 85 examined patients. 24 of them (group 1) were diagnosed with COVID-19 infection with typical clinical symptoms 3-9 months ago, and 25 (group 2) had no clinical manifestations of the acute respiratory infection at the appropriate time suggesting an asymptomatic course of the disease. IgM class antibodies were detected with equal frequency in group 1 and in group 2 (33.3 vs 24.0%, respectively, p<0.6). IgG antibodies exclusively to the nucleocapsid N-protein (IgGn) were detected only in the latent form of the disease (32%), while antibodies against the S-protein (spike protein) of the virus (IgGs and IgGn+s) were detected more often in the manifest form compared to the asymptomatic one (100 vs 60%, respectively, p<0.05). Conclusion. In a random cohort of patient receiving hemodialysis treatment, more than half were asymptomatic.Despite a wide range of prevention measures, SARS-CoV-2 infection among patients treated with hemodialysis is more than 2 times higher than in the general population.Copyright © 2021 Geotar Media Publishing Group. All rights reserved.

Features of the Humoral Response to Infection, Vaccination, and Revaccination during COVID-19.

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 patients with long-term persistent IgM antibodies, no coronavirus antigens were detected. After vaccination with the Gam-COVID-Vac vaccine, IgG antibodies to the S-protein are detected in 100% of cases and remain at a high level for 4 months, by the 5-6th month, the level of antibodies decreases. During revaccination, the level of IgG antibodies to S-protein reaches high values earlier than during primary vaccination, and remains high for 4 months (observation period). The blood sera of recovered and vaccinated patients have a high virus-neutralizing activity (at least 1:80), while its level is somewhat higher in recovered patients.

Therapeutic efficacy of antibody drugs in patients with severe viral infections and COVID-19

The review summarizes information on the therapeutic efficacy of antibody preparations in severe viral infections with a detailed analysis of their activity in COVID-19. The pathogenesis and drug therapy of coronavirus infection are briefly considered. Medicinal properties of blood plasma of convalescents and possible reasons for its insufficient, in some cases, efficiency are analyzed. Various points of view on the advisability of creating and using hyperimmune drugs containing a high titer of antibodies to COVID-19 are discussed. On the example of gabriglobin, a domestic immunoglobulin for intravenous administration, which has a high therapeutic activity in hemorrhagic fever with renal syndrome, cytomegalovirus infection, atypical pneumonia and septic conditions, it is hypothesized that for the treatment of many severe viral diseases, including COVID-19, it is possible to use of conventional, "normal" immunoglobulin preparations, which have a population-averaged antibody titer and many cross-reacting antibodies to a wide range of infectious agents. Copyright © 2022, Dynasty Publishing House. All rights reserved.

Seroprevalence of anti-sars-cov-2 antibodies among healthcare professionals in Moscow in april-december 2020

We evaluated humoral immunity (presence of specific IgM and IgG) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among healthcare professionals providing inpatient care for individuals with COVID-19. Objective. To detected and measure the level of anti-SARS-CoV-2 antibodies in healthcare professionals and to identify how many of them contacted with COVID-19 patients, including those who had asymptomatic or subclinical disease. Materials and methods. Anti-SARS-CoV-2 antibodies were detected using enzyme-linked immunosorbent assay (ELISA) with the ‘SARS-CoV-2-ELISA-Vector’ kit for IgG (State research Center of Virology and Biotechnology ‘Vector’) and ‘SARS-CoV-2-IgG- ELISA-BEST’ and ‘SARS-CoV-2-IgМ-ELISA-BEST’ kits for IgM and IgG (Vector-Best LLC). Samples were collected in several healthcare institutions of Moscow and in G.N.Gabrichevskiy Moscow Research Institute of Epidemiology and Microbiology. A total of 24,373 serum specimens from 74 healthcare institutions were tested. All study participants filled in special questionnaires. Results. Among 24,373 healthcare professionals tested in this study, 5,382 people were IgG-positive to SARS-CoV-2 (seroprevalence index 22.1%). The seropositivity rate was 21.5% in senior medical staff, 22.2% in nursing professionals, and 22.8% in medical assistants/technicians. We found that the proportion of SARS-CoV-2 seropositive individuals had changed over time, gradually increasing from 17.9% in April 2020 to 37.6% in December 2020. The proportion of SARS-CoV-2 seropositive people doubled among senior medical staff and nursing professionals during the year. The proportion of individuals with asymptomatic or subclinical COVID-19 was 13.8%. Conclusion. The methodological approaches used in this study allowed us to assess the humoral immunity to SARS-CoV-2 among healthcare professionals in Moscow. Our findings can be used for further improvement of anti-epidemic measures in healthcare institutions. © 2021, Dynasty Publishing House. All rights reserved.

Dynamics of Antibodies to Various Antigens of the SARS-CoV-2 Coronavirus in Patients with Confirmed COVID-19 Infection.

The presence of IgG and IgM antibodies in the venous blood of 76 patients with confirmed COVID-19 infection was determined by ELISA using Russian test systems. Different levels of IgM antibodies to N-protein and receptor binding domain of the Spike protein (RBD) were revealed. The dynamics of IgG antibodies to the whole virion antigen and recombinant antigens showed high values on weeks 4-5 of the disease. The level of IgG antibodies to Nprotein remained low throughout the observation period. The characteristic dynamics of IgG measured using test systems with sorbed whole virion or recombinant spike proteins reflects the duration of the disease.

Frequency of SARS-CoV-2 infection in hemodialysis patients

Patients with end-stage chronic kidney disease treated with hemodialysis are at risk of infection and severe course of the new coronavirus infection. This opinion was based on the data obtained as a result of PCR testing during the active phase of the disease with detailed clinical symptoms. However, this diagnostic method does not allow one to fully assess the prevalence of infection in the population. The aim – studying of the frequency of SARS-CoV-2 infection in patients receiving hemodialysis treatment and the spectrum of antiviral antibodies, depending on the nature of the course of COVID-19. Material and methods. 100 patients with chronic kidney disease (stage 5D) treated at the outpatient Dialysis Center (MCVTP) were included in the study by a simple random sample. The assessment of SARS-CoV-2 infection was carried out by analyzing the material of smears obtained from the naso-oropharynx by PCR and blood serum samples by ELISA. The study excluded 14 patients with dubious results for the determination of serological markers SARS-CoV-2 and 1 patient with active infection, who was isolated from the RNA of the virus. Results. IgM and IgG antibodies were detected in 49 (57.6%) of the 85 examined patients. 24 of them (group 1) were diagnosed with COVID-19 infection with typical clinical symptoms 3–9 months ago, and 25 (group 2) had no clinical manifestations of the acute respiratory infection at the appropriate time suggesting an asymptomatic course of the disease. IgM class antibodies were detected with equal frequency in group 1 and in group 2 (33.3 vs 24.0%, respectively, p<0.6). IgG antibodies exclusively to the nucleocapsid N-protein (IgGn) were detected only in the latent form of the disease (32%), while antibodies against the S-protein (spike protein) of the virus (IgGs and IgGn+s) were detected more often in the manifest form compared to the asymptomatic one (100 vs 60%, respectively, p<0.05). Conclusion. In a random cohort of patient receiving hemodialysis treatment, more than half were asymptomatic.Despite a wide range of prevention measures, SARS-CoV-2 infection among patients treated with hemodialysis is more than 2 times higher than in the general population. © 2021 Geotar Media Publishing Group. All rights reserved.