[Clinical characteristics of children infected with SARS-CoV-2 Omicron variant combined with allergic disease].

Objective: To investigate the clinical characteristics of children with allergic diseases suffering from SARS-CoV-2 Omicron variant strains. Methods: This was a cross-sectional study. A total of 43 pediatric patients with allergic diseases infected by SARS-CoV-2 from April 25, 2022 to June 8, 2022 in Shanghai Jiao Tong University School of Medicine were selected as the allergic disease group, while 114 cases without underlying diseases and 16 cases with other underlying diseases were selected as control groups diagnosed at the same period. Clinical data including clinical features, laboratory tests, duration of hospitalization, and the time to negative turn of novel coronavirus nucleic acid were collected and analysed. Kruskal-Wallis H test, chi-square test or Fisher exact test were used for comparison among three groups. Results: Among the 43 patients with allergic diseases, 28 were males and 15 were females, with an age of 4.4 (2.1, 8.2) years on admission, including 32 mild cases and 11 common cases. The allergic disease group included 20 cases (46.5%) of atopic dermatitis and eczema, followed by 14 cases (32.6%) of rhinitis, 8 cases (18.6%) of food allergies, 7 cases (16.3%) of asthma, 4 cases (9.3%) of allergic conjunctivitis and 2 cases (4.7%) of drug allergy. Among the 114 cases without underlying diseases, 57 were males and 57 were females, with an age of 2.8 (1.2, 5.6) years on admission, including 93 mild cases and 21 common cases. Among the 16 cases with other underlying diseases, 9 were males and 7 were females, with an age of 3.0 (2.6, 10.8) years on admission, including 13 cases mild and 3 cases common cases. Children with allergic diseases had higher frequency of sore throat and vomiting than those without underlying diseases (10 cases (23.3%) vs.9 cases (7.9%), 14 cases (32.6%) vs. 11 cases (9.6%), χ²=6.93, 12.24, both P<0.05). The lymphocyte count of patients with allergic disease was lower than those without underlying disease (1.1 (0.7,1.7)×109 vs. 1.6 (1.1,2.7)×109/L, H=-28.00,P=0.005). There were no significant differences in age, gender, typing of SARS-CoV-2, the duration of hospitalization, cycle threshold values of SARS-CoV-2 and the time to negative turn of novel coronavirus nucleic acid among the three groups (all P>0.05). Conclusions: Children with allergic diseases may suffer from sore throat and vomiting more frequently when infected with SARS-CoV-2 Omicron variant. The combination of allergic diseases hardly influenced the disease course of SARS-CoV-2 in children.

Characterization of SARS-CoV-2-Specific Humoral and Cellular Immune Responses Induced by Inactivated COVID-19 Vaccines in a Real-World Setting

While the immunogenicity of inactivated vaccines against coronavirus disease 2019 (COVID-19) has been characterized in several well-conducted clinical trials, real-world evidence concerning immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raised by such vaccines is currently missing. Here, we comprehensively characterized various parameters of SARS-CoV-2-specific cellular and humoral immune responses induced by inactivated COVID-19 vaccines in 126 individuals under real-world conditions. After two doses of vaccination, S-receptor binding domain IgG (S-RBD IgG) and neutralizing antibody (NAb) were detected in 87.06% (74/85) and 78.82% (67/85) of individuals, respectively. Female participants developed higher concentrations of S-RBD IgG and NAb compared to male vaccinees. Interestingly, a longer dosing interval between the first and second vaccination resulted in a better long-term SARS-CoV-2 S-RBD IgG response. The frequencies of CD4+ T cells that produce effector cytokines (IFN-gamma, IL-2, and TNF-alpha) in response to stimulation with peptide pools corresponding to the SARS-CoV-2 spike (S), nucleocapsid (N) or membrane (M) protein were significantly higher in individuals received two doses of vaccine than those received one dose of vaccine and unvaccinated individuals. S, N, or M-specific CD4+ and CD8+ T cell responses were detectable in 95.83% (69/72) and 54.16% (39/72) of double-vaccinated individuals, respectively. The longitudinal analysis demonstrated that CD4+ T cell responses recognizing S, N, and M waned quickly after a single vaccine dose, but were boosted and became more sustained following a second dose. Overall, we provide a comprehensive characterization of immune responses induced by inactivated COVID-19 vaccines in real-world settings, suggesting that both humoral and cellular SARS-CoV-2 specific immunity are elicited in the majority of individuals after two doses of inactivated COVID-19 vaccines.

[Characteristics and related factors of viral nucleic acid negative conversion in children infected with Omicron variant strain of SARS-CoV-2].

Objective: To understand the characteristics and associated factors of viral nucleic acid conversion in children infected with Omicron variant strain of SARS-CoV-2 in Shanghai. Methods: The clinical symptoms, laboratory results and other data of 177 children infected with SARS-CoV-2 who were hospitalized in Shanghai Children's Hospital, School of Medicine, Shanghai Jiao Tong University (designated hospital for SARS-CoV-2 infection in Shanghai) from April 25 to June 8, 2022 were retrospectively analyzed. According to the chest imaging findings, the children were divided into mild and common type groups. According to their age, the unvaccinated children were divided into<3 years old group and 3-<18 years old group. According to the vaccination status, the children aged 3-<18 year were divided into non-vaccination group, 1-dose vaccination group and 2-dose vaccination group. Comparison between groups was performed by independent sample t-test and analysis of variance, and multivariate linear regression analysis was used for multivariate analysis. Results: Among the 177 children infected with Omicron variant of SARS-CoV-2, 96 were males and 81 were females, aged 3 (1, 6) years. The time of viral nucleic acid negative conversion was (10.3±3.1) days. The 177 children were 138 cases of mild type and 39 cases of common type. Among the children aged 3-<18 years old, 55 cases were not vaccinated, 5 cases received 1-dose and 36 cases received 2-dose vaccination. Among the 36 children who received 2 doses of vaccination, the time of viral nucleic acid negative conversion was shorter in those vaccinated within 6 months than those over 6 months ((7.1±1.9) vs. (10.8±3.0) d, t=-3.23, P=0.004). Univariate analysis showed that the time of nucleic acid negative conversion of SARS-CoV-2 was associated with age, underlying diseases, gastrointestinal symptoms, white blood cell count, proportion of neutrophils, proportion of lymphocytes, and the number of doses of SARS-CoV-2 vaccine (t=3.87, 2.55, 2.04, 4.24, 3.51, 2.92, F=16.27, all P<0.05). Multiple linear regression analysis showed that older age (ß=-0.33, 95% CI -0.485--0.182, P<0.001) and more doses of vaccination (ß=-0.79, 95% CI -1.463--0.120, P=0.021) were associated with shortened nucleic acid negative conversion time in children, while lower lymphocyte proportion (ß=-0.02, 95% CI -0.044--0.002, P=0.031) and underlying diseases (ß=1.52, 95% CI 0.363-2.672, P=0.010) were associated with prolonged nucleic acid negative conversion time in children. Conclusion: The children infected with Omicron variant of SARS-CoV-2 with reduced lymphocyte proportion and underlying diseases may have longer time of viral nucleic acid negative conversion,while children with older age and more doses of vaccination may have shorter time of viral nucleic acid negative conversion.

[COVID-19 treated with oral Nirmatrelvir-Ritonavir in 3 children].

Objective: To summarize the application experience and the therapeutic effect of Nirmatrelvir-Ritonavir (trade name: Paxlovid) for COVID-19 in children. Methods: A retrospective analysis was performed on the clinical data, including collecting the clinical manifestations and clinical outcomes, dynamically monitoring the blood routine, hepatic and renal function and SARS-CoV-2 nucleic acid results, and observing the related side effects during the treatment, etc, of 3 cases with COVID-19 treated with Paxlovid admitted to Shanghai Children's Hospital (designated referral hospital for SARS-CoV-2 infection in Shanghai) from May 1st to June 1st, 2022. Results: The 3 cases were 12, 14, 17 years of age, among which 2 cases were males, 1 case was female. All 3 cases were mild cases with underlying diseases and risk of developing into severe COVID-19, with symptoms of high fever, sore throat and dry cough. The treatment of Paxlovid at 3rd day of symptom onset contributed to the symptom-free after 1-2 days and negative results of SARS-CoV-2 nucleic acid after 2-4 days. All patients had no adverse manifestations of gastrointestinal tract and nervous system but a case had little skin rashes, which recovered after the withdrawal of Paxlovid. Three cases had normal hepatic and renal function during the Paxlovid treatment. At 3 months after discharge, no clinical manifestations of post-COVID syndrome were found in all 3 cases. Conclusion: Paxlovid was effective and relatively safe in the treatment of 3 children with COVID-19.

Smartphone recognition-based immune microparticles for rapid on-site visual data-sharing detection of Newcastle disease virus

Since the last century, animal viruses have posed great threats to the health of humans and the farming industry. Therefore, virus control is of great urgency, and regular, timely, and accurate detection is essential to it. Here, we designed a rapid on-site visual data-sharing detection method for the Newcastle disease virus with smartphone recognition-based immune microparticles. The detection method we developed includes three major modules: preparation of virus detection vectors, sample detection, and smartphone image analysis with data upload. First, the hydrogel microparticles containing active carboxyl were manufactured, which coated nucleocapsid protein of NDV. Then, HRP enzyme-labeled anti-NP nanobody was used to compete with the NDV antibody in the serum for color reaction. Then the rough detection results were visible to the human eyes according to the different shades of color of the hydrogel microparticles. Next, the smartphone application was used to analyze the image to determine the accurate detection results according to the gray value of the hydrogel microparticles. Meanwhile, the result was automatically uploaded to the homemade cloud system. The total detection time was less than 50 min, even without trained personnel, which is shorter than conventional detection methods. According to experimental results, this detection method has high sensitivity and accuracy. And especially, it uploads the detection information via a cloud platform to realize data sharing, which plays an early warning function. We anticipate that this rapid on-site visual data-sharing detection method can promote the development of virus selfchecking at home.

Information-sharing mechanism of synergistic incentive among EPC subjects of energy efficiency retrofitting of existing buildings against COVID-19

The pandemic situation of COVID-19 blocks many traditional information exchange paths, intensifies the information asymmetry in the implementation of the energy efficiency retrofitting project of existing building and seriously affects the decision-making effect of the energy performance contracting (EPC) subject. Therefore, based on the information-sharing platform, this paper constructs the synergistic incentive framework;designs the computational experimental models from the aspects of system information structure, system organization structure, synergistic communication strategy and subject knowledge structure;and analyzes the influence mechanism and evolution law of information on synergistic incentive performance from the two dimensions of the influence of the synergy cycle on the incentive performance and the influence of the incentive cycle on the synergy degree. The results show that increasing the information redundancy length and the information redundancy width can improve the synergy degree and incentive validity. The concentration of subject number or information dimension in a certain information area can quickly improve the synergy degree and incentive utility in the early stage of the synergistic incentive cycle, but the above situation is opposite in the later stage. Increasing the information communication path is beneficial to the effective information dissemination among subjects and can improve the efficiency of the decision-making of the subjects. Lastly, considering the background of COVID-19 epidemic situation, this paper puts forward the remedial methods and coping strategies make up for the lack of synergistic incentive information between EPC subjects. Research results can provide strong support for the design of synergistic incentive mechanism of EPC subjects.

Modeling the emergence of COVID-19: a systems approach

In December 2019, a novel coronavirus disease (COVID-19) suddenly emerged in Wuhan, China. In March 2020, WHO declares the coronavirus outbreak a pandemic. The virus has spread quickly to all over China and most of the countries and regions within the increasing urbanization and globalization, infected more than three million people worldwide. A crucial factor that may significantly affect the spread of COVID-19 is the multiple, interactive, emergent, and complex characteristics and systems of the social systems. This paper describes a systems approach modeling and analyzing the emergence and spread of COVID-19 in urban systems, seeking to combine the multi-layer urban structure between complex infrastructure systems, human activities and policy systems. Moreover, a complex network model is built to illustrate the diffusion of the virus with or without the intervention of policy systems under the different policy intensity by the changed basic reproduction number (R-0). Besides, a system dynamics model, including feedback loops and changes, is proposed to demonstrate how the COVID-19 spreads out under the interactive and interrelated characteristics and systems of the complex systems at different levels.

[Research advances in the mechanism of pulmonary fibrosis induced by coronavirus disease 2019 and the corresponding therapeutic measures].

Coronavirus disease 2019 (COVID-19) outbroke in Wuhan, China in December 2019 and the severe acute respiratory syndrome (SARS) outbroke in Guangzhou, China in 2003 were caused by highly pathogenic coronaviruses with high homology. Since the 2019 novel coronavirus is highly contagious and spreads rapidly. It has caused negative social effects and massive economic loss globaly. Currently there is no vaccine or effective drugs. Pulmonary fibrosis is a pulmonary disease with progressive fibrosis, which is the main factor leading to pulmonary dysfunction and declined quality of life in SARS survivors after recovery. Extensive epidemiological, viral immunological and current clinical evidences support the possibility that pulmonary fibrosis may be one of the major complications in COVID-19 patients. At present there is no report on the mechanism by which COVID-19 induces pulmonary fibrosis.With the existing theoretical basis, this article focuses on discussing the possible mechanism of COVID-19 sustained lung damaging, the key role of abnormal immune mechanism in the initiation and promotion of pulmonary fibrosis, and the corresponding therapeutic measures.