Clinical and immunological parallels in children patients with COVID-19

The problem of the incidence of new coronavirus infection in childhood is becoming increasingly important. At the same time, questions arise regarding the peculiarities of the pathogenesis of COVID-19 in children. The aim of the research was to study the clinical and immunological features of COVID-19 in children hospitalized with a severe course of the disease. Material and methods. We examined 53 children from 0 to 15 years old, hospitalized with suspected new coronavirus infection at Children's Clinical Hospital No. 3 in Novosibirsk from October to December 2020. Determination of specific IgM and IgG antibodies to SARS-CoV-2 antigens in serum blood was carried out using the ELISA method. SARS-CoV-2 virus RNA in nasopharyngeal and oropharyngeal swabs was determined using commercial kits for PCR diagnostics. A z-test was used to compare relative numbers. The significance level was taken equal to 5% (p=0.05). Results and discussion. All examined children hospitalized with suspected COVID-19, regardless of the duration of the disease, had specific IgG antibodies to SARS-CoV-2 antigens, which confirms earlier contact with the new coronavirus in relation to the time of the examination. In 63.6% of cases, specific IgM antibodies of the class to SARS-CoV-2 were detected in the blood serum, in 6% of cases the result was doubtful. IgM antibodies were not detected in blood serum in 30.3% of patients. The results obtained for the determination of IgG and IgM antibodies to SARS-CoV-2 antigens may reflect the atypical nature of seroconversion in COVID-19. An extremely diverse clinical symptomatology was revealed, including, in addition to catarrhal syndrome and intoxication syndrome, abdominal, meningeal, and articular syndromes. In 24.3% of children, polymorphic exanthema was detected, which may be a manifestation of the systemic nature of damage to the vascular wall. Conclusion. With serologically confirmed SARS-CoV-2 etiology of the infectious process in the examined children, an extremely diverse clinical symptomatology was revealed, which, most likely, may be associated with multiple organ damage.Copyright © Transplantologiya. The Russian Journal of Transplantation.All right reserved.

Features of laboratory parameters in children with multisystem inflammatory syndrome associated with SARS-CoV-2

Multisystem inflammatory syndrome (MIS-C) is a new childhood disease associated with coronavirus SARS-CoV-2 that manifests itself 3–4 weeks after infection. The development of MIS-C is possible, despite the asymptomatic course of coronavirus infection. The pathogenetic features of MIS-C remain unclear. The aim of the study was to investigate the state of peripheral blood parameters in children with multisystem inflammatory syndrome associated with SARS-CoV-2 upon admission to a hospital. Material and methods. We examined 52 children with MIS-C from 1 to 14 years old, hospitalized in Children`s Clinical Hospital No. 3 in Novosibirsk in October–December 2020. Testing for the isolation of SARS-CoV-2 RNA in scrapings from the nasopharynx and oropharynx was carried out using real time PCR (test systems of DNA-Technology, Russia). The presence of specific IgM and IgG antibodies to SARS-CoV-2 in blood serum was determined by ELISA using Vector-Best kits (Russia). Results and discussion. It was noted that SARS-CoV-2 virus RNA was found only in 12.8 % of cases, while specific IgG antibodies in blood serum were detected in 100 % of children. IgM to SARS-CoV-2 antigens were detected in the blood serum only in 53.85 % of children with MIS-C. It has been established that unexpressed leukocytosis was found both in children under the age of 7 and in children of 8–14 years old. However, the leukocytes content in children of the older age group was significantly lower than in children aged 1–7 years. At the same time, in both age groups, some children had extremely low values of the indicator. The causes of severe leukopenia against the background of excessive inflammation remain unclear. Age groups (1–7 and 8–14 years) do not differ statistically significantly in the relative content of lymphocytes and neutrophils. In the study of individual values of the relative content of lymphocytes within the age groups, it was noted that only some children had lymphopenia of varying severity. Conclusions. Against the background of minor leukocytosis in children with MIS-C, upon admission to the hospital, there is a tendency to develop both relative and absolute lymphopenia, regardless of age. The study noted an extremely pronounced variability of individual values of the evaluated peripheral blood parameters, regardless of age, which, with similar clinical symptoms, characterized as MIS-C, requires further study in dynamics, taking into account the initial values of the indicators.There is no pronounced relationship between the leukocytes content and specific IgM antibodies to SARS-CoV-2 antigens in the blood. © 2022, Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences. All rights reserved.

Plasma metabolomics and gene regulatory networks analysis reveal the role of nonstructural SARS-CoV-2 viral proteins in metabolic dysregulation in COVID-19 patients.

Metabolomic analysis of blood plasma samples from COVID-19 patients is a promising approach allowing for the evaluation of disease progression. We performed the metabolomic analysis of plasma samples of 30 COVID-19 patients and the 19 controls using the high-performance liquid chromatography (HPLC) coupled with tandem mass spectrometric detection (LC-MS/MS). In our analysis, we identified 103 metabolites enriched in KEGG metabolic pathways such as amino acid metabolism and the biosynthesis of aminoacyl-tRNAs, which differed significantly between the COVID-19 patients and the controls. Using ANDSystem software, we performed the reconstruction of gene networks describing the potential genetic regulation of metabolic pathways perturbed in COVID-19 patients by SARS-CoV-2 proteins. The nonstructural proteins of SARS-CoV-2 (orf8 and nsp5) and structural protein E were involved in the greater number of regulatory pathways. The reconstructed gene networks suggest the hypotheses on the molecular mechanisms of virus-host interactions in COVID-19 pathology and provide a basis for the further experimental and computer studies of the regulation of metabolic pathways by SARS-CoV-2 proteins. Our metabolomic analysis suggests the need for nonstructural protein-based vaccines and the control strategy to reduce the disease progression of COVID-19.

Photodynamic inactivation of SARS-CoV-2 on inanimate surfaces

Since coronaviruses can remain infectious on different inanimate surfaces for several hours or even days, the possibility of indirect fomite transmission through infected objects and surfaces cannot be ruled out. We describe a method for the photodynamic disinfection of inanimate surfaces infected with severe acute respiratory syndrome coronavirus 2, Omicron variant strain. Application of only 5 mu M photosensitizer octakis(cholinyl)zinc phthalocyanine followed immediately by 7 min irradiation with light emitting diode (LED) light 692 nm (12.5 mW cm(-2)) results in complete inactivation of the virus on polystyrene and glass surfaces, while 10 min irradiation lead to complete eradication of the virus also on Al-foil and medical mask fabric. A photodynamic technique is being considered to combat the spread of coronaviruses.

Assessment of the effectiveness of medical rehabilitation after COVID-19 based on the functional capacity of the cardiovascular and respiratory systems

Aim. To assess the effectiveness of medical rehabilitation after pneumonia associated with the novel coronavirus infection (COVID-19), based on the study of functional capacity of the cardiovascular system and the external respiratory system. Methods. The study included 70 patients who had COVID-19 pneumonia and underwent a medical rehabilitation program from September to December 2020. Before being included in the rehabilitation program, all patients underwent pulmonary function tests (PFT), including an assessment of the lungs diffusion capacity, cardiopulmonary exercise testing, multispiral computed tomography (MSCT) of the chest, echocardiography, an evaluation of the quality of life according to the SF-36 questionnaire and the severity of shortness of breath on the mMRC scale. The effectiveness of rehabilitation was evaluated against the changes in PFT parameters, exercise tolerance, and quality of life. Results. At the enrollment, 46% of patients retained lung tissue lesions shown by MSCT and accompanied by a decrease in the lung diffusion capacity (67 (55 – 79%) of predicted value), dyspnea of 1.6 (1.0 – 3.0) points according to mMRC scale, moderate level of exercise tolerance and quality of life. Complex cardiopulmonary rehabilitation for 12 – 14 days in a specialized hospital led to a significant improvement in the parameters of pulmonary gas exchange and ventilation, peak oxygen consumption, and an increase in the reserve capacity of the cardiorespiratory system. The factors limiting the improvement of pulmonary gas exchange were the older age of the patients and the increased pressure in the pulmonary artery system. The positive influence of rehabilitation on both the physical and psycho-emotional components of the quality of life was noted. Conclusion. Complex cardiopulmonary rehabilitation with the assessment of changes in the oxygen metabolism parameters and functional capacity of the cardiovascular and respiratory systems has shown to be safe and highly effective in the studied group of patients who have had COVID-19 pneumonia. © 2021 Medical Education. All rights reserved.

Wild Animal Migration As a Potential Threat of Introduction of New Viruses into Russia.

The SARS-CoV-2 pandemic has shown how serious the problem of re-emerging zoonotic infections is for our existence. Migrations of animals, which are natural reservoirs of a particular virus, play a colossal role in the spread of pathogens to new territories. Examples are the migrations of both land animals (carnivores, rodents, and ungulates) and many marine mammals (pinnipeds and cetaceans). Yet the most interesting from the point of view of the speed and range of the spread of viral infections are migrations associated with flights. In nature, these can be migrations of insects, bats, and, of course, birds. Unfortunately, there are very few studies on the migration of these animals in Russia. Considering the problems related to climate change and other environmental factors, it is important to obtain up-to-date data on the changing animal migration routes and, as a consequence, to develop domestic equipment, particularly transmitters, to fix them.

Cell and Organism Technologies for Assessment of the SARS-CoV-2 Infectivity in Fluid Environment.

Under conditions of COVID-19 pandemic, considerable amounts of SARS-CoV-2 contained in household, municipal, and medical wastewaters inevitably reach natural water bodies. Possible preservation of virus infectivity in liquid environment is of a paramount epidemiological importance. Experiments demonstrated that SARS-CoV-2 is resistant to multiple freezing/thawing cycles and retains its infectivity in tap and river water for up to 2 days at 20°C and 7 days at 4°C. In natural milk, its viability is preserved in a refrigerator for 6 days. The exposure of aquarium fish to the virus-containing water fails to cause any infection.

Clinical and immunological parallels in children patients with COVID-19

The problem of the incidence of new coronavirus infection in childhood is becoming increasingly important. At the same time, questions arise regarding the peculiarities of the pathogenesis of COVID-19 in children. The aim of the research was to study the clinical and immunological features of COVID-19 in children hospitalized with a severe course of the disease. Material and methods. We examined 53 children from 0 to 15 years old, hospitalized with suspected new coronavirus infection at Children's Clinical Hospital No. 3 in Novosibirsk from October to December 2020. Determination of specific IgM and IgG antibodies to SARS-CoV-2 antigens in serum blood was carried out using the ELISA method. SARS-CoV-2 virus RNA in nasopharyngeal and oropharyngeal swabs was determined using commercial kits for PCR diagnostics. A z-test was used to compare relative numbers. The significance level was taken equal to 5% (p=0.05). Results and discussion. All examined children hospitalized with suspected COVID-19, regardless of the duration of the disease, had specific IgG antibodies to SARS-CoV-2 antigens, which confirms earlier contact with the new coronavirus in relation to the time of the examination. In 63.6% of cases, specific IgM antibodies of the class to SARS-CoV-2 were detected in the blood serum, in 6% of cases the result was doubtful. IgM antibodies were not detected in blood serum in 30.3% of patients. The results obtained for the determination of IgG and IgM antibodies to SARS-CoV-2 antigens may reflect the atypical nature of seroconversion in COVID-19. An extremely diverse clinical symptomatology was revealed, including, in addition to catarrhal syndrome and intoxication syndrome, abdominal, meningeal, and articular syndromes. In 24.3% of children, polymorphic exanthema was detected, which may be a manifestation of the systemic nature of damage to the vascular wall. Conclusion. With serologically confirmed SARS-CoV-2 etiology of the infectious process in the examined children, an extremely diverse clinical symptomatology was revealed, which, most likely, may be associated with multiple organ damage. © Transplantologiya. The Russian Journal of Transplantation.All right reserved.

Development of a Purified Viral Preparation for Studies of COVID-19 (SARS-CoV-2) Biology.

Different methods for producing bulk quantities of concentrated and purified SARS-CoV-2 for the use as antigens and for the research into COVID-19 biology were tested.

Antigenic properties of sARs-CoV-2/human/RUs/nsk-FRCFtM-1/2020 coronavirus isolate from a patient in novosibirsk

Objective: isolation of coronavirus SARS-CoV-2 from clinical sample of patient with COVID-19 in Novosibirsk;obtaining a purified and inactivated viral antigen and study of its antigenic properties. Materials and methods: virus isolation was carried out in Vero cell culture from nasopharyngeal swab positive on SARS-CoV-2 RNA. The efficiency of SARS-CoV-2 replication in cell culture was assessed on the appearance of cytopathic effect (CPE) and the presence of viral RNA in cultural medium with reverse transcription – polymerase chain reaction (RT-PCR). Purification, concentration and inactivation of the viral preparation were carried out according to standard methods. The purity of the purified preparation and the profile of viral proteins were determined by electrophoresis in 10% polyacrylamide gel (PAG) with the addition of sodium dodecyl sulfate (SDS). The presence and specificity of viral proteins were detected using COVID-19 convalescent’s sera with enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Results: SARS-CoV-2/human/ RUS/Nsk-FRCFTM-1/2020 isolate was obtained after passage on Vero cells from a virus-containing clinical sample. A purified, concentrated, inactivated, whole-virion antigen was obtained. It contains three structural proteins: glycoprotein S (approximately 200 kDa), nucleoprotein N (48 kDa), and matrix protein M (20-25 kDa). All viral proteins were detected with serum antibodies of COVID-19 convalescents. Conclusion: SARS-CoV-2 coronavirus can be isolated in Vero cell culture. The antigenic specificity of the three structural viral proteins (S, N, and M) is preserved in the purified inactivated viral preparation. The inactivated whole-virion antigen of SARS-CoV-2/human/RUS/Nsk-FRCFTM-1/2020 isolate can be used to study the antigenic immunomodulating properties of viral proteins, to obtain immune sera of laboratory animals, and also as a component of test systems for the detection of specific antibodies with ELISA and immunoblotting.