The Reduction of SARS-CoV-2 RNA Concentration in the Presence of Sewer Biofilms

Wastewater surveillance has been widely used to track the prevalence of SARS-CoV-2 in communities. Although some studies have investigated the decay of SARS-CoV-2 RNA in wastewater, understanding about its fate during wastewater transport in real sewers is still limited. This study aims to assess the impact of sewer biofilms on the dynamics of SARS-CoV-2 RNA concentration in naturally contaminated real wastewater (raw influent wastewater without extra SARS-CoV-2 virus/gene seeding) using a simulated laboratory-scale sewer system. The results indicated that, with the sewer biofilms, a 90% concentration reduction of the SARS-CoV-2 RNA was observed within 2 h both in wastewater of gravity (GS, gravity-driven sewers) and rising main (RM, pressurized sewers) sewer reactors. In contrast, the 90% reduction time was 8–26 h in control reactors without biofilms. The concentration reduction of SARS-CoV-2 RNA in wastewater was significantly more in the presence of sewer biofilms. In addition, an accumulation of c.a. 260 and 110 genome copies/cm2 of the SARS-CoV-2 E gene was observed in the sewer biofilm samples from RM and GS reactors within 12 h, respectively. These results confirmed that the in-sewer concentration reduction of SARS-CoV-2 RNA in wastewater was likely caused by the partition to sewer biofilms. The need to investigate the in-sewer dynamic of SARS-CoV-2 RNA, such as the variation of RNA concentration in influent wastewater caused by biofilm attachment and detachment, was highlighted by the significantly enhanced reduction rate of SARS-CoV-2 RNA in wastewater of sewer biofilm reactors and the accumulation of SARS-CoV-2 RNA in sewer biofilms. Further research should be conducted to investigate the in-sewer transportation of SARS-CoV-2 and their RNA and evaluate the role of sewer biofilms in leading to underestimates of COVID-19 prevalence in communities.

CpG 684: an effective adjuvant for the inactivated COVID-19 vaccine in mice

Aim: This study used CpG 684 as adjuvant of inactivated COVID-19 vaccine to detect a humoral and cellular immune response in mice. Materials & methods: We used 10 and 20 µg CpG 684 as adjuvants of am inactivated COVID-19 vaccine to immunize mice. IgG, IgG1, IgG2a, IgG2b and IgM binding antibodies were detected in serum by ELISA. The IFN-γ cytokine was detected by ELISPOT. Results: CpG 684 improved spike-specific IgG and IgM subtype binding antibodies and increased the neutralizing antibody titer against prototype, Delta and Beta strains. CpG 684 also improved cellular immune response. Conclusion: CpG 684 is an effective adjuvant for inactivated COVID-19 vaccine.

Risk factors associated with indoor transmission during home quarantine of COVID-19 patients.

Purpose: The study aimed to identify potential risk factors for family transmission and to provide precautionary guidelines for the general public during novel Coronavirus disease 2019 (COVID-19) waves. Methods: A retrospective cohort study with numerous COVID-19 patients recruited was conducted in Shanghai. Epidemiological data including transmission details, demographics, vaccination status, symptoms, comorbidities, antigen test, living environment, residential ventilation, disinfection and medical treatment of each participant were collected and risk factors for family transmission were determined. Results: A total of 2,334 COVID-19 patients participated. Compared with non-cohabitation infected patients, cohabitated ones were younger (p = 0.019), more commonly unvaccinated (p = 0.048) or exposed to infections (p < 0.001), and had higher rates of symptoms (p = 0.003) or shared living room (p < 0.001). Risk factors analysis showed that the 2019-nCov antigen positive (OR = 1.86, 95%CI 1.40-2.48, p < 0.001), symptoms development (OR = 1.86, 95%CI 1.34-2.58, p < 0.001), direct contact exposure (OR = 1.47, 95%CI 1.09-1.96, p = 0.010) were independent risk factors for the cohabitant transmission of COVID-19, and a separate room with a separate toilet could reduce the risk of family transmission (OR = 0.62, 95%CI 0.41-0.92, p = 0.018). Conclusion: Patients showing negative 2019-nCov antigen tests, being asymptomatic, living in a separate room with a separate toilet, or actively avoiding direct contact with cohabitants were at low risk of family transmission, and the study recommended that avoiding direct contact and residential disinfection could reduce the risk of all cohabitants within the same house being infected with COVID-19.

The mediating role of coping strategies between depression and social support and the moderating effect of the parent–child relationship in college students returning to school: During the period of the regular prevention and control of COVID-19

Objective According to the WHO, compared to before the COVID-19 pandemic, young people showed a significant increase in depressive symptoms. In light of the recent coronavirus pneumonia pandemic, this study was conducted to determine how social support, coping style, parent-child relationships, and depression are associated. We investigated how these factors interacted and affected the prevalence of depression during this challenging and unheard-of time. Our research may help both individuals and healthcare professionals better comprehend and assist those who are coping with the pandemic's psychological effects. Design and main outcome measures 3,763 students from a medical college in Anhui Province were investigated with Social Support Rate Scale, Trait Coping Style Questionnaire, and Self-rating Depression Scale. Results When the pandemic situation was normalizing, social support was associated with depression and the coping style of college students (p < 0.01). During the period of pandemic normalization, the parent–child relationship moderated the relationship between social support and positive coping (t = −2.45, p < 0.05);the parent–child relationship moderated the relationship between social support and negative coping (t = −4.29, p < 0.01);and the parent–child relationship moderated the association between negative coping and depression (t = 2.08, p < 0.05). Conclusion Social support has an impact on depression in the period of the regular prevention and control of COVID-19 through the mediating role of coping style and the moderating effect of the parent–child relationship.

Candida parapsilosis infection after double-lung transplantation in a patient with pulmonary fibrosis caused by COVID-19.

Pulmonary fibrosis is a complication in patients with coronavirus disease 2019 (COVID-19). Extensive pulmonary fibrosis is a severe threat to patients' life and lung transplantation is last resort to prolong the life of patients. We reported a case of critical type COVID-19 patient, though various treatment measures were used, including anti-virus, anti-infection, improving immunity, convalescent plasma, prone position ventilation, and airway cleaning by fiber-optic bronchoscope, although his COVID-19 nucleic acid test turned negative, the patient still developed irreversible extensive pulmonary fibrosis, and respiratory mechanics suggested that lung compliance could not be effectively recovered. After being assisted by ventilator and extracorporeal membrane oxygenation for 73 days, he finally underwent double-lung transplantation. On the 2nd day after the operation, the alveolar lavage fluid of transplanted lung was examined by cytomorphology, and the morphology of alveolar epithelial cells was intact and normal. On the 20th day post-transplantation, the chest radiograph showed a large dense shadow in the middle of the right lung. On the 21st day, the patient underwent fiber-optic bronchoscopy, yeast-like fungal spores were found by cytomorphological examination from a brush smear of the right bronchus, which was confirmed as Candida parapsilosis infection by fungal culture. He recovered well due to the careful treatment and nursing in our hospital. Until July 29, 96 days after transplantation, the patient was recovery and discharged from hospital.

Flexible Amperometric Immunosensor Based on Colloidal Quantum Dots for Detecting the Myeloperoxidase (MPO) Systemic Inflammation Biomarker.

Myeloperoxidase (MPO) has been demonstrated to be a biomarker of neutrophilic inflammation in various diseases. Rapid detection and quantitative analysis of MPO are of great significance for human health. Herein, an MPO protein flexible amperometric immunosensor based on a colloidal quantum dot (CQD)-modified electrode was demonstrated. The remarkable surface activity of CQDs allows them to bind directly and stably to the surface of proteins and to convert antigen-antibody specific binding reactions into significant currents. The flexible amperometric immunosensor provides quantitative analysis of MPO protein with an ultra-low limit of detection (LOD) (31.6 fg mL-1), as well as good reproducibility and stability. The detection method is expected to be applied in clinical examination, POCT (bedside test), community physical examination, home self-examination and other practical scenarios.

Prevalence of taste and smell dysfunction in mild and asymptomatic COVID-19 patients during Omicron prevalent period in Shanghai, China: a cross-sectional survey study.

OBJECTIVES: COVID-19, which is caused by SARS-CoV-2, is a severe threat to human health and the economy globally. This study aimed to investigate the prevalence of taste and/or smell dysfunction and associated risk factors in mild and asymptomatic patients with Omicron infection in Shanghai, China.DesignThis was a questionnaire-based cross-sectional study. SETTING: COVID-19 patients at the makeshift hospital in the Shanghai World Expo Exhibition and Convention Centre were recruited from March to April 2022. PARTICIPANTS: In total, 686 COVID-19-infected patients who were defined as mild or asymptomatic cases according to the diagnostic criteria of New Coronavirus Pneumonia Prevention and Control Programme ninth edition (National Health Commission of China, 2022) were enrolled. MEASURES: Data to investigate taste and smell loss and to characterise other symptoms were collected by the modified Chemotherapy-induced Taste Alteration Scale and Sino-Nasal Outcome Test-22 questionnaires. The risk factors for the severity of taste/smell dysfunction were analysed by binary logistic regression models. RESULTS: 379 males (379/686, 55.2%) and 307 females (307/686, 44.8%) completed the questionnaires to record recent changes in taste and smell ability. A total of 302 patients (44%) had chemosensory dysfunction with Omicron infection, of which 22.7% (156/686) suffered from both taste and smell dysfunction. In addition, cough (60.2%), expectoration (40.5%), fever (33.2%) and sore throat (32.5%) were common symptoms during Omicron infection. The quality-of-life-related indicators were negatively associated with participants' self-reported taste and smell dysfunction. CONCLUSIONS: The prevalence of taste or/and smell dysfunction in patients with Omicron infections was 44%. Individuals with chemosensory dysfunction had significantly higher rates of various upper respiratory influenza-like symptoms, xerostomia and bad breath. Moreover, smell dysfunction was a risk factor for the prevalence of taste dysfunction in patients with Omicron infection. TRIAL REGISTRATION NUMBER: ChiCTR 2200059097.

The mediating role of coping strategies between depression and social support and the moderating effect of the parent-child relationship in college students returning to school: During the period of the regular prevention and control of COVID-19.

Objective: According to the WHO, compared to before the COVID-19 pandemic, young people showed a significant increase in depressive symptoms. In light of the recent coronavirus pneumonia pandemic, this study was conducted to determine how social support, coping style, parent-child relationships, and depression are associated. We investigated how these factors interacted and affected the prevalence of depression during this challenging and unheard-of time. Our research may help both individuals and healthcare professionals better comprehend and assist those who are coping with the pandemic's psychological effects. Design and main outcome measures: 3,763 students from a medical college in Anhui Province were investigated with Social Support Rate Scale, Trait Coping Style Questionnaire, and Self-rating Depression Scale. Results: When the pandemic situation was normalizing, social support was associated with depression and the coping style of college students (p < 0.01). During the period of pandemic normalization, the parent-child relationship moderated the relationship between social support and positive coping (t = -2.45, p < 0.05); the parent-child relationship moderated the relationship between social support and negative coping (t = -4.29, p < 0.01); and the parent-child relationship moderated the association between negative coping and depression (t = 2.08, p < 0.05). Conclusion: Social support has an impact on depression in the period of the regular prevention and control of COVID-19 through the mediating role of coping style and the moderating effect of the parent-child relationship.

Moving forward with COVID-19: Future research prospects of wastewater-based epidemiology methodologies and applications.

Wastewater-based epidemiology (WBE) has been demonstrated for its great potential in tracking of coronavirus disease 2019 (COVID-19) transmission among populations despite some inherent methodological limitations. These include non-optimized sampling approaches and analytical methods; stability of viruses in sewer systems; partitioning/retention in biofilms; and the singular and inaccurate back-calculation step to predict the number of infected individuals in the community. Future research is expected to (1) standardize best practices in wastewater sampling, analysis and data reporting protocols for the sensitive and reproducible detection of viruses in wastewater; (2) understand the in-sewer viral stability and partitioning under the impacts of dynamic wastewater flow, properties, chemicals, biofilms and sediments; and (3) achieve smart wastewater surveillance with artificial intelligence and big data models. Further specific research is essential in the monitoring of other viral pathogens with pandemic potential and subcatchment applications to maximize the benefits of WBE beyond COVID-19.

Patients with IBD have a more cautious attitude towards COVID-19 vaccination.

Background: To understand the awareness of COVID-19 vaccine, the willingness to vaccinate and the influencing factors of willingness to vaccinate in inflammatory bowel disease (IBD) patients. Methods: The online questionnaire was distributed to conduct a survey to analyze and evaluate the willingness, awareness and trust in vaccines of IBD patients. Bivariate analyses and logistic regression models were used to analysis influencing factors. Results: We sent the questionnaire to the WeChat group for patient management and 304 patients responded, out of which 16 respondents had to be excluded and 288 respondents were included for the analysis. Among them, 209 patients vaccinated with COVID-19 vaccine. Among the non-vaccinated 79 patients, the main reasons for their concerns were afraid of vaccination aggravating IBD and fear of adverse effects. Our results showed that IBD patients with long disease duration were more willing to receive COVID-19 vaccination (P<0.05). We also observed that a high perception of benefits and cues to action to receive the vaccine were the two most important constructs affecting a definite intention for COVID-19 vaccination (P<0.05). Conclusions: Patients with IBD have a more cautious attitude towards COVID-19 vaccination, which may lead to a higher rate of vaccine hesitancy. Further efforts should be made to protect patients with IBD from COVID-19 infections and achieve adequate vaccination coverage.

Nutritional metabolism evaluation and image segmentation of the chicken muscle and internal organs for automatic evisceration.

The chicken is rich in various proteins, fatty acids, polysaccharides, trace elements, and other human essential nutrients that contribute to its high nutritional value. In this study, the expression levels of nutrition-related genes (acetyl-CoA acyltransferase, ACAA) of native chicken breeds were investigated. The level of GgalACAA1-2 transcripts expression in the liver of chicken was significantly higher than that of muscle and heart. Moreover, three protein extracts were isolated from the muscle, heart, and liver tissues from the chicken, and their nutritional function was evaluated in the present study. These protein extracts had excellent DPPH and hydroxyl radical scavenging capacities and exhibited significant superoxide anion scavenging ability. Moreover, the protein extracts of muscle tissue showed an important mouse splenocyte proliferation activity and could be used as an immunomodulator of natural origin. In addition, this report presented an automatic visual inspection of chicken viscera using the active contour algorithms and the image processing method for eviscerating by the parallel robot. The recognition and positioning rate of chicken viscera obtained by the proposed method could reach 96.45%. These methods provided basic data for automated poultry slaughter and segmentation, avoiding unnecessary health risks by a pathogenic microorganism, such as avian influenza, Newcastle disease virus, and coronavirus. Moreover, the internal organs of the chicken could be fully harvested by the image segmentation of automatic evisceration, which also facilitated the processing value of these internal organs as by-products of poultry.

Patients with IBD have a more cautious attitude towards COVID-19 vaccination

Background To understand the awareness of COVID-19 vaccine, the willingness to vaccinate and the influencing factors of willingness to vaccinate in inflammatory bowel disease (IBD) patients. Methods The online questionnaire was distributed to conduct a survey to analyze and evaluate the willingness, awareness and trust in vaccines of IBD patients. Bivariate analyses and logistic regression models were used to analysis influencing factors. Results We sent the questionnaire to the WeChat group for patient management and 304 patients responded, out of which 16 respondents had to be excluded and 288 respondents were included for the analysis. Among them, 209 patients vaccinated with COVID-19 vaccine. Among the non-vaccinated 79 patients, the main reasons for their concerns were afraid of vaccination aggravating IBD and fear of adverse effects. Our results showed that IBD patients with long disease duration were more willing to receive COVID-19 vaccination (P<0.05). We also observed that a high perception of benefits and cues to action to receive the vaccine were the two most important constructs affecting a definite intention for COVID-19 vaccination (P<0.05). Conclusions Patients with IBD have a more cautious attitude towards COVID-19 vaccination, which may lead to a higher rate of vaccine hesitancy. Further efforts should be made to protect patients with IBD from COVID-19 infections and achieve adequate vaccination coverage.

Discovery of Novel Chinese Medicine Compounds Targeting 3CL Protease by Virtual Screening and Molecular Dynamics Simulation.

The transmission and infectivity of COVID-19 have caused a pandemic that has lasted for several years. This is due to the constantly changing variants and subvariants that have evolved rapidly from SARS-CoV-2. To discover drugs with therapeutic potential for COVID-19, we focused on the 3CL protease (3CLpro) of SARS-CoV-2, which has been proven to be an important target for COVID-19 infection. Computational prediction techniques are quick and accurate enough to facilitate the discovery of drugs against the 3CLpro of SARS-CoV-2. In this paper, we used both ligand-based virtual screening and structure-based virtual screening to screen the traditional Chinese medicine small molecules that have the potential to target the 3CLpro of SARS-CoV-2. MD simulations were used to confirm these results for future in vitro testing. MCCS was then used to calculate the normalized free energy of each ligand and the residue energy contribution. As a result, we found ZINC15676170, ZINC09033700, and ZINC12530139 to be the most promising antiviral therapies against the 3CLpro of SARS-CoV-2.

Willingness of college students to receive COVID-19 heterologous vaccination in Taizhou, China.

This study aimed to determine the willingness of college students to choose COVID-19 heterologous vaccination and its associated influencing factors in Taizhou, China. A population-based, self-administered online questionnaire was conducted from March 15 to 17, 2022. Of the 2,463 participants who had received the invitation, 1,821 responded to the survey (response rate = 73.9%). Only 14% (86/614) of those willing to receive a booster would chose a heterologous vaccination; the perception of better effectiveness of a COVID-19 heterologous vaccination booster was the significant factor (X2 = 22.671, p < .001). Additionally, female college students'older age (χ2 = 7.523, P = .023), major of medical (χ2 = 6.294, P = .012), and better perceived effectiveness of COVID-19 heterologous vaccination booster (χ2 = 22.659, P < .001), were more willing to receive heterologous booster doses. Chinese college students have a strong willingness to receive booster shots, but the percentage of those willing to receive a heterologous vaccine is only 14.0%, and the lack of understanding of its effectiveness is an important factor in the low proportion of heterologous vaccine selection. Health education, public health awareness, and the disclosure of heterologous vaccine information can help improve the public's understanding of heterologous vaccines and provide them with more choices.

Tetrahedral DNA framework assisted rotational paper-based analytical device for differential detection of SARS-CoV-2 and influenza A H1N1 virus.

Coronavirus disease 2019 (COVID-19) and influenza A are two respiratory infectious diseases with similar clinical manifestations. Because of the complex global epidemic situation of COVID-19, the distinction and diagnosis of COVID-19 and influenza A infected persons is crucial for epidemic prevention and control. In this study, tetrahedral DNA framework (TDF) was combined with a rotational paper-based analytical device, and the color change generated by the reaction between horseradish peroxidase (HRP) and 3,3'5,5'-tetramethylbenzidine (TMB)-H2O2 was used for grayscale signal analysis by ImageJ software. The quantitative detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza A H1N1 virus were realized simultaneously. Under the optimal conditions, the paper-based analytical device showed a good linear relationship between the two viruses in the range of 10-14-10-8g/mL, and the two viruses were not affected by cross reaction. This sensor provides a convenient and reliable method for clinical rapid differentiation and diagnosis of COVID-19 and influenza A.

COVID-19 vaccination influences subtypes of γδ-T cells during pregnancy.

Up to now, there has been insufficient clinical data to support the safety and effects of vaccination on pregnancy post COVID-19 vaccination. The γδ-T cells are considered an important component in the immune system to fight against viral infection and exhibit critical roles throughout the pregnancy period. However, the immunological roles of γδ-T cells in pregnant women with the COVID-19 vaccination remain unclear. Therefore, the objective of this study is to investigate the alteration of frequency and expression pattern of activation receptors and inhibitory receptors in γδ-T cell and its subsets in peripheral blood samples collected from non-pregnant vaccinated women, vaccinated pregnant women, and unvaccinated pregnant women. Our findings indicated that the frequency of CD3+γδ-T+ cells is lower in vaccinated pregnant women than in unvaccinated pregnant women. But no significant difference was found in the frequency of CD3+γδ-T+ cells between non-pregnant vaccinated women and vaccinated pregnant women. In addition, there were no significant differences in the frequencies of CD3+γδ-T+Vδ1+T cells, CD3+γδ-T+Vδ2+T cells, CD3+γδ-T+Vδ1-Vδ2-T cells, and Vδ1+T cell/Vδ2+T cell ratio between the pregnant women with or without COVID-19 vaccination. Similar results were found after comparing non-pregnant and pregnant women who received the COVID-19 vaccine. However, there was a significant difference in the fraction of Vδ1-Vδ2-T cells in CD3+γδ-T+ cells between non-pregnant vaccinated women and vaccinated pregnant women. The frequency of NKG2D+ cells in Vδ2+T cells was not significantly different in the vaccinated pregnant women when compared to that in unvaccinated pregnant women or non-pregnant vaccinated women. But the percentage of NKG2D+ cells in Vδ1+T cells was the lowest in pregnant women after COVID-19 vaccination. Furthermore, down-regulation of NKP46 and NKP30 were found in Vδ2+T and Vδ1+T cells in the vaccinated pregnant women, respectively. After the vaccination, up-regulation of PD-1 expression in Vδ1+T cells and Vδ2+T cells indicated γδ-T cells could respond to COVID-19 vaccination and display an exhausted phenotype following activation. In conclusion, COVID-19 vaccination influences subtypes of γδ-T cells during pregnancy, but the side effects might be limited. The phenotypical changes of Vδ1+T cells and Vδ2+T cells will be a promising predictor for evaluating the clinical outcome of the COVID-19 vaccine.

Evaluations of COVID-19 epidemic models with multiple susceptible compartments using exponential and non-exponential distribution for disease stages.

Mathematical models have wide applications in studying COVID-19 epidemic transmission dynamics, however, most mathematical models do not take into account the heterogeneity of susceptible populations and the non-exponential distribution infectious period. This paper attempts to investigate whether non-exponentially distributed infectious period can better characterize the transmission process in heterogeneous susceptible populations and how it impacts the control strategies. For this purpose, we establish two COVID-19 epidemic models with heterogeneous susceptible populations based on different assumptions for infectious period: the first one is an exponential distribution model (EDM), and the other one is a gamma distribution model (GDM); explicit formula of peak time of the EDM is presented via our analytical approach. By data fitting with the COVID-19 (Omicron) epidemic in Spain and Norway, it seems that Spain is more suitable for EDM while Norway is more suitable for GDM. Finally, we use EDM and GDM to evaluate the impaction of control strategies such as reduction of transmission rates, and increase of primary course rate (PCR) and booster dose rate (BDR).

A functional RNA/DNA circuit for one-pot detection of SARS-CoV-2 RNA.

A simple method is proposed in this work for the detection of SARS-CoV-2 RNA based on a functional RNA/DNA circuit. By ingeniously integrating the nucleic acid circuit technology and CRISPR/cas12a system, this method can achieve femtomolar detection of the target RNA in one step and successfully distinguish COVID-19 positive cases from clinical samples, proving its great potential for clinical application.