Differentially Private Computation of Basic Reproduction Numbers in Networked Epidemic Models (preprint)

The basic reproduction number of a networked epidemic model, denoted $R_0$, can be computed from a network's topology to quantify epidemic spread. However, disclosure of $R_0$ risks revealing sensitive information about the underlying network, such as an individual's relationships within a social network. Therefore, we propose a framework to compute and release $R_0$ in a differentially private way. First, we provide a new result that shows how $R_0$ can be used to bound the level of penetration of an epidemic within a single community as a motivation for the need of privacy, which may also be of independent interest. We next develop a privacy mechanism to formally safeguard the edge weights in the underlying network when computing $R_0$. Then we formalize tradeoffs between the level of privacy and the accuracy of values of the privatized $R_0$. To show the utility of the private $R_0$ in practice, we use it to bound this level of penetration under privacy, and concentration bounds on these analyses show they remain accurate with privacy implemented. We apply our results to real travel data gathered during the spread of COVID-19, and we show that, under real-world conditions, we can compute $R_0$ in a differentially private way while incurring errors as low as $7.6\%$ on average.

Pandemic Exposure and Adolescent Anxiety: Roles of Negative Media Exposure and Negative Coping Styles (preprint)

The COVID-19 pandemic threatened people’s mental health, especially for adolescents, because their adjustment mechanisms of cognition and emotion are not perfect. They are more likely to have psychological health problems such as anxiety. The existing researches have carried out relevant discussions on this issue, indicating that excessive exposure to public health emergency events and negative coping styles are important factors causing psychological and behavioral problems such as anxiety. In this study, self-report questionnaires were distributed to 983 middle school students from Hubei province in China. This study focused on the role of negative media exposure and negative coping styles, so as to reveal the mechanism of adolescent anxiety during the pandemic. The results showed that pandemic exposure had a predicative effect on adolescent anxiety. The mechanism of this effect included the direct effect of pandemic exposure, the indirect effect of negative media exposure and negative coping styles.

Privacy-Preserving Video Conferencing via Thermal-Generative Images (preprint)

Due to the COVID-19 epidemic, video conferencing has evolved as a new paradigm of communication and teamwork. However, private and personal information can be easily leaked through cameras during video conferencing. This includes leakage of a person's appearance as well as the contents in the background. This paper proposes a novel way of using online low-resolution thermal images as conditions to guide the synthesis of RGB images, bringing a promising solution for real-time video conferencing when privacy leakage is a concern. SPADE-SR (Spatially-Adaptive De-normalization with Self Resampling), a variant of SPADE, is adopted to incorporate the spatial property of a thermal heatmap and the non-thermal property of a normal, privacy-free pre-recorded RGB image provided in a form of latent code. We create a PAIR-LRT-Human (LRT = Low-Resolution Thermal) dataset to validate our claims. The result enables a convenient way of video conferencing where users no longer need to groom themselves and tidy up backgrounds for a short meeting. Additionally, it allows a user to switch to a different appearance and background during a conference.

Evaluation of antibody kinetics and durability in health subjects vaccinated with inactivated COVID-19 vaccine (CoronaVac): A cross-sectional and cohort study in Zhejiang, China (preprint)

Background: Although inactivated COVID-19 vaccines are proven to be safe and effective in the general population, the dynamic response and duration of antibodies after vaccination in the real world should be further assessed. Methods: We enrolled 1067 volunteers who had been vaccinated with one or two doses of CoronaVac in Zhejiang Province, China. Another 90 healthy adults without previous vaccinations were recruited and vaccinated with three doses of CoronaVac, 28 days and 6 months apart. Serum samples were collected from multiple timepoints and analyzed for specific IgM/IgG and neutralizing antibodies (NAbs) for immunogenicity evaluation. Antibody responses to the Delta and Omicron variants were measured by pseudovirus-based neutralization tests. Results: Our results revealed that binding antibody IgM peaked 14-28 days after one dose of CoronaVac, while IgG and NAbs peaked approximately 1 month after the second dose then declined slightly over time. Antibody responses had waned by month 6 after vaccination and became undetectable in the majority of individuals at 12 months. Levels of NAbs to live SARS-CoV-2 were correlated with anti-SARS-CoV-2 IgG and NAbs to pseudovirus, but not IgM. Homologous booster around 6 months after primary vaccination activated anamnestic immunity and raised NAbs 25.5-fold. The NAb inhibition rate subsequently rose to 36.0% for Delta (p=0.03) and 4.3% for Omicron (p=0.004), and the response rate for Omicron rose from 7.9% (7/89) to 17.8% (16/90). Conclusions: Two doses of CoronaVac vaccine resulted in limited protection over a short duration. The homologous booster slightly increased antibody responses to the Delta and Omicron variants; therefore, the optimization of booster procedures is vital. Funding: Key Research and Development Program of Zhejiang Province; Key Program of Health Commission of Zhejiang Province/ Science Foundation of National Health Commission; Major Program of Zhejiang Municipal Natural Science Foundation.

Immunogenicity and safety of a SARS-CoV-2 inactivated vaccine (CoronaVac) co-administered with an inactivated quadrivalent influenza vaccine: A randomized, open-label, controlled study in healthy adults aged 18 to 59 years in China.

BACKGROUND: Studies are needed for evidence of inactivated COVID-19 vaccine co-administered with influenza vaccine. METHODS: A randomized, open-label, controlled study was conducted in Zhejiang Province, China. Eligible healthy adults aged 18-59 years underwent randomization at a ratio of 1:1:2 to receive inactivated quadrivalent influenza vaccine (IIV4) either concomitantly with the first (C1 subgroup) or the second (C2 subgroup) dose of CoronaVac, or 14 days after the first dose of CoronaVac (S group). The primary purpose of the study was to prove the non-inferiority in seroconversion rate of antibody against SARS-CoV-2. RESULTS: Overall, 480 participants were enrolled, with 120, 120, and 240 randomly assigned to the C1, C2, and S groups, respectively. As lower bound of the two-sided 95% confidence interval (CI) of the difference for the seroconversion rate of antibodies against SARS-CoV-2 was over -10%, the immune response for CoronaVac in the C group (93.1% [89.0, 96.0]) was non-inferior to that in the S group (95.2% [91.5, 97.6]) in the per-protocol set. A lower GMT of antibody against SARS-CoV-2 was observed in the C group as compared to the S group (27.5 vs. 38.1, P = 0.0001). Decrease of immune response to CoronaVac was mainly observed in participants received IIV4 concomitantly with their second dose of CoronaVac (C2 subgroup), with a seroconversion rate of 89.7% (95CI: 82.6%-94.5%) and a GMT of 23.3. The occurrences of vaccine related adverse reactions were no more than 20% and comparable among different groups. Most of the adverse reactions were mild and moderate. CONCLUSION: Co-administration of inactivated COVID-19 vaccine and seasonal influenza vaccine, especially the administration regimen that the seasonal influenza vaccine co-administered with the first dose of the inactivated COVID-19 vaccine, would be feasible.

One Novel Phantom-Less Quantitative Computed Tomography System for Auto-Diagnosis of Osteoporosis Utilizes Low-Dose Chest Computed Tomography Obtained for COVID-19 Screening.

Background: The diagnosis of osteoporosis is still one of the most critical topics for orthopedic surgeons worldwide. One research direction is to use existing clinical imaging data for accurate measurements of bone mineral density (BMD) without additional radiation. Methods: A novel phantom-less quantitative computed tomography (PL-QCT) system was developed to measure BMD and diagnose osteoporosis, as our previous study reported. Compared with traditional phantom-less QCT, this tool can conduct an automatic selection of body tissues and complete the BMD calibration with high efficacy and precision. The function has great advantages in big data screening and thus expands the scope of use of this novel PL-QCT. In this study, we utilized lung cancer or COVID-19 screening low-dose computed tomography (LDCT) of 649 patients for BMD calibration by the novel PL-QCT, and we made the BMD changes with age based on this PL-QCT. Results: The results show that the novel PL-QCT can predict osteoporosis with relatively high accuracy and precision using LDCT, and the AUC values range from 0.68 to 0.88 with DXA results as diagnosis reference. The relationship between PL-QCT BMD with age is close to the real trend population (from ∼160 mg/cc in less than 30 years old to ∼70 mg/cc in greater than 80 years old for both female and male groups). Additionally, the calculation results of Pearson's r-values for correlation between CT values with BMD in different CT devices were 0.85-0.99. Conclusion: To our knowledge, it is the first time for automatic PL-QCT to evaluate the performance against dual-energy X-ray absorptiometry (DXA) in LDCT images. The results indicate that it may be a promising tool for individuals screened for low-dose chest computed tomography.

Summary of global surveillance data of infectious diseases in December 2021

In December 2021, a total of 64 infectious diseases were reported globally, affecting 228 countries and regions. Except for influenza, the top five infectious diseases affecting greatest number of countries and regions were corona virus disease 2019 (COVID-19, 228), measles (29), dengue fever (28), cholera (12) and chikungunya fever (9). The top five infectious diseases with highest case fatality rates were Ebola virus disease (81.8%), Middle East respiratory syndrome (34.4%), yellow fever (22.0%), Lassa fever (20.0%) and plague (10.8%). The top five infectious diseases with greatest number of deaths were COVID-19, malaria, measles, dengue fever and cholera. The prevalent infectious diseases in Asia were COVID-19 and dengue fever, the prevalent infectious diseases in Africa were COVID-19, cholera, yellow fever, plague, Lassa fever, poliomyelitis, malaria and measles, the prevalent infectious diseases in America were COVID-19, dengue fever, chikungunya fever and Zika virus disease, the prevalent infectious disease in Europe was COVID-19.

Broadly neutralizing and protective nanobodies against diverse sarbecoviruses (preprint)

As SARS-CoV-2 Omicron and other variants of concern continue spreading around the world, development of antibodies and vaccines to confer broad and protective activity is a global priority. Here, we report on the identification of a special group of nanobodies from immunized alpaca with exceptional breadth and potency against diverse sarbecoviruses including SARS-CoV-1, Omicron BA.1, and BA.2. Crystal structure analysis of one representative nanobody, 3-2A2-4, revealed a highly conserved epitope between the cryptic and the outer face of the receptor binding domain (RBD). The epitope is readily accessible regardless of RBD in up or down conformation and distinctive from the receptor ACE2 binding site. Passive delivery of 3-2A2-4 protected K18-hACE2 mice from infection of authentic SARS-CoV-2 Delta and Omicron. This group of nanobodies and the epitope identified should provide invaluable reference for the development of next generation antibody therapies and vaccines against wide varieties of SARS-CoV-2 infection and beyond.

Zinc Intakes and Health Outcomes: An Umbrella Review

It is widely accepted that the zinc element is crucial in human beings. Zinc has gained more attention during the COVID-19 pandemic due to its utilization for the treatment and prevention of respiratory tract infections. However, some studies also pointed out that zinc intake might cause unwanted side effects and even be dangerous when overdosed. To reveal the relationship between zinc intake and health outcomes, we performed an umbrella review from human studies. In total, the umbrella review included 43 articles and identified 11 outcomes for dietary zinc intake and 86 outcomes for supplementary zinc intake. Dietary zinc intake in the highest dose would decrease the risk of overall and specific digestive tract cancers, depression, and type 2 diabetes mellitus (T2DM) in adults. Supplementary zinc consumption in adults was linked to an improvement of depression, antioxidant capacity and sperm quality, higher serum zinc concentration, and lower concentration of inflammatory markers. Zinc supplementation in children would reduce the incidence of diarrhea and pneumonia, improve zinc deficiency and boost growth. However, zinc might not decrease all-cause mortality in adults or the in-hospital mortality of COVID-19. And better maternal and neonatal outcomes may not derive from pregnant women who consumed higher or lower doses of zinc supplementation (>20 mg/day and <20 mg/day, respectively). Dose-response analyses revealed that a daily 5 mg increment of zinc would lower the risk of colorectal and esophageal cancer, whereas a large dose of zinc supplementation (daily 100 mg) showed no benefit in reducing prostate cancer risk.

Teaching Evolution: The Use of Social Networking Sites

Online schooling has been adopted worldwide due to the COVID-19 pandemic. During quarantine, people go online for all kind of purposes, especially for amusement such as via social networking sites (SNSs). This study examined university physical education (PE) students’SNSs usage intention using the Unified Theory of Acceptance and Use of Technology model II (UTAUT2) in Taiwan. Research respondents were selected from PE departments of 19 universities through purposive sampling method. A total of 707 questionnaires were collected, with a returning rate of 93%. Using Warp PLS 7.0 as the main instrument for data analysis, this research finds that performance expectancy, facilitating conditions, hedonic motivation, price value, and habit within the UTAUT2 model have significant positive effects on students’intention to use social networking sites, and the model explains 63.4% of the variance in their intention to use SNSs. Among those variables, hedonic motivation had the highest impact (β= 0.24). Moreover, intention, facilitating conditions and habit have significant positive effects on students’use of social networking sites, and the model explains 13.4% of the variance in their use of social networking sites. The moderating effects of gender, age and experience are found in some path analyses. These findings provide future university instructors a with better understanding of students using SNSs. We thus recommend for university PE instructors to create interesting and pleasant classroom learning experiences to attract students’attention, and recommend that they may even manage a SNS as an aid for teaching to enhance students’interests in learning.

Prevalence and Predictors of Anxiety and Depressive Symptoms Among International Medical Students in China During COVID-19 Pandemic.

Background: The rapid spread of Coronavirus Disease-19 (COVID-19) infection has been the most important public health crisis across the globe since the end of 2019. Anxiety and depression are the most common mental health problems among people during the pandemic, and many studies have reported anxiety and depressive symptoms in college students. However, information on the mental health status of international medical students during this critical period of time has been scarce, which hinders the efforts in making proper policy or strategies to help these students. The present study aims to explore the prevalence of anxiety and depressive symptoms in international medical students in China and to find out the factors that have potential predictive value for anxiety and depressive symptoms. Method: A cross-sectional study was carried out for international medical students during November 2020 at China Medical University in Shenyang, China. Five hundred and nineteen international students were interviewed with questionnaires containing demographic variables, Stressors in school, Generalized Anxiety Disorder Assessment (GAD-7), Patient Health Questionnaire-9 (PHQ-9), Simplified Coping Style Questionnaire (SCSQ), Perceived Stress Scale (PSS-10), the Multidimensional Scale of Perceived Social Support (MSPSS), Revised Life Orientation Test (LOT-R) and Resilience Scale-14 (RS-14). Univariate logistic regression and stepwise multiple logistic regression analyses were conducted where appropriate to explore the predictive factors of anxiety symptoms and depressive symptoms. Results: The prevalence of anxiety symptoms and depressive symptoms in the sample population was 28.5% (148/519) and 31.6% (164/519), respectively. Stressors in school (ß = 0.176, OR = 1.192, CI: 1.102-1.289), negative coping style (ß = 0.639, OR = 1.894, CI: 1.287-2.788) and perceived stress (ß = 0.230, OR = 1.258, CI: 1.184-1.337) were found to be the predictors of anxiety symptoms among the international medical students; while gender (ß = -0.594, OR = 0.552, CI: 0.315-0.968), stay up late (ß = 0.828, OR = 2.288, CI: 1.182-4.431), current place of residence (ß = 1.082, OR = 2.951, CI: 1.256-6.931), stressors in the school (ß = 0.303, OR = 1.354, CI: 1.266-1.496), negative coping style (ß = 0.866, OR = 2.377, CI: 1.516-3.725), perceived stress (ß = 0.233, OR = 1.262, CI: 1.180-1.351) were found to be predictors of depressive symptoms. Conclusion: The prevalence of anxiety symptoms and depressive symptoms was moderate among international medical students in China. The communal predictors of anxiety and depressive symptoms were stressors in school, negative coping style and perceived stress; while demographic factors such as gender (male), stay up late at night and current place of residence were found associated with depressive symptoms. These results suggest that proper stress management and specific interventions are needed to help students maintain their mental health during the COVID-19 pandemic period.

An overview of COVID-19

Pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection emerged in Wuhan City, Hubei Province, China in December 2019. By Feb. 11, 2020, the World Health Organization (WHO) officially named the disease resulting from infection with SARS-CoV-2 as coronavirus disease 2019 (COVID-19). COVID-19 represents a spectrum of clinical manifestations that typically include fever, dry cough, and fatigue, often with pulmonary involvement. SARS-CoV-2 is highly contagious and most individuals within the population at large are susceptible to infection. Wild animal hosts and infected patients are currently the main sources of disease which is transmitted via respiratory droplets and direct contact. Since the outbreak, the Chinese government and scientific community have acted rapidly to identify the causative agent and promptly shared the viral gene sequence, and have carried out measures to contain the epidemic. Meanwhile, recent research has revealed critical aspects of SARS-CoV-2 biology and disease pathogenesis;other studies have focused on epidemiology, clinical features, diagnosis, management, as well as drug and vaccine development. This review aims to summarize the latest research findings and to provide expert consensus. We will also share ongoing efforts and experience in China, which may provide insight on how to contain the epidemic and improve our understanding of this emerging infectious disease, together with updated guidance for prevention, control, and critical management of this pandemic.

Culture, Institution, and COVID-19 First-Response Policy: A Qualitative Comparative Analysis of Thirty-One Countries

Different from existing studies focusing on formal institutional factors, this study applies a configurational approach to exploring how cultural, institutional, and crisis-specific factors interplay to shape policymaking under extremely uncertain and risky circumstances. A fuzzy-set qualitative comparative analysis of the COVID-19 first-response policies adopted by 31 countries reveals three pathways consistently leading to a more stringent first response, whereas the other two pathways consistently contributed to a less stringent one. The study advances comparative policy analysis by illuminating multiple configurations of cultural, institutional, and pandemic-specific factors that have shaped policymaking during the COIVD-19 pandemic. [ABSTRACT FROM AUTHOR] Copyright of Journal of Comparative Policy Analysis is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Locked on Salt? Excessive Consumption of High-sodium Foods during COVID-19 Presents an Underappreciated Public Health Risk (preprint)

Abrupt changes in food preferences and eating habits pose an overlooked public health risk during the coronavirus disease (COVID-19) pandemic. Emerging evidence suggests an ongoing, population-level shift to consumption of high-sodium foods, during COVID-19 and lockdowns, in the general population surveyed in different countries and cultures. High-sodium foods are defined as those with sodium contents exceeding 500 mg per 100 g, and many processed and preserved foods fall into this particular category. Excessive dietary sodium intake is associated with chronic diseases including hypertension, cardiovascular diseases, and kidney diseases, and poses confounding risks during COVID-19. Here, we review food categories in consumers’ shopping lists and food parcels delivered to those who need assistance during the current pandemic, when frozen meals, canned foods, instant foods, snacks, and other high-sodium foods gained substantial popularity. Such emerging trends in consumers’ behavior are driven by a multitude of factors. Specifically, the perceived risk of COVID-19 infection in grocery shopping trips, limited supplies and inflated prices of fresh produce, preference on foods with long shelf lives, emotional eating, and the general low awareness of sodium contents in food have all contributed to the increased consumption of high-sodium foods during COVID-19. We also discuss the possible effects on COVID-19 infection and severity caused by excessive sodium intake, by reviewing current reports and hypotheses examining their relations. In light of the evidence, it is advisable to educate the public to maintain a healthy sodium intake during the current pandemic, and measures could be adopted by governments and private donors in procuring food parcels with more balanced sodium contents to lower the risks of prolonged and excessive sodium intakes in vulnerable population groups.

Disinfectant- and Antibiotic-Resistance in Community Environments and Risk of Direct Transfers to Humans: Unintended Consequences of Community-Wide Surface Disinfecting during COVID-19? (preprint)

During the current pandemic, chemical disinfectants are ubiquitously and routinely used in community environments, especially on common touch surfaces in public settings, as a means of controlling the virus spread. An underappreciated risk in current regulatory guidelines and scholarly discussions, however, is that the persisting input of chemical disinfectants can exacerbate the growth of disinfectant- and antibiotic-resistant bacteria on those surfaces and allow their direct transfers to humans. For COVID-19, the most commonly used disinfecting agents are quaternary ammonium, hydrogen peroxide, sodium hypochlorite, and ethanol, which account for two-thirds of the active ingredients in current EPA-approved disinfectant products for the novel coronavirus. Resistance to each of these compounds, which can be either intrinsic or exogenously acquired, has been observed on various bacterial pathogens. Of those, upregulation of efflux pumps, cell membrane modification, and biofilm formation are three common mechanisms promoting disinfectant resistance in bacteria. Further, some disinfectants and disinfection byproducts also promote antibiotic resistance and give rise to multidrug resistant bacteria. Evidence showed that substantial bacterial transfers to hands could effectuate from short contacts with surrounding surfaces and further from the fingers to lips. While current literature on disinfectant-induced antimicrobial resistance predominantly focuses on municipal wastes and the natural environments, in reality the community and public settings are most severely impacted by intensive and regular chemical disinfecting during COVID-19 and, due to their proximity to humans, disinfectant-and-antibiotic resistant bacteria emerged in these environments may pose risks of direct transfers to humans, particularly in densely populated urban communities. Here we highlight these risk factors by reviewing the most pertinent and up-to-date evidence, and provide several feasible strategies to mitigate these risks in the scenario of a prolonging pandemic.

Early Treatment Effect of Chinese Herbal Medicine Formula Huashibaidu Granule on Mild COVID-19 Patients in Fangcang Hospital: An Unblinded, Cluster-Randomized Clinical Trial (preprint)

BACKGROUND: Previous study suggested that Chinese Herbal Medicine (CHM) Formula Huashibaidu granule might shorten disease course of Corona Virus Disease 2019 (COVID-19) patients. Our research aims to investigate the early treatment effect of Huashibaidu granule in mild COVID-19 patients under well clinical management.METHODS: An unblended cluster-randomized clinical trial was conducted at the Dongxihu FangCang hospital. 2 cabins were randomly allocated to CHM or control group, with 204 randomly sampled mild COVID-19 patients in each cabin. All participants received a 7-day conventional treatment, and CHM group cabin used additional Huashibaidu granule 10g twice daily. Participants were followed up until they met clinical endpoint. The primary outcome was patient become worsening before clinical endpoint occurred. The secondary outcomes was discharge with cure before clinical endpoint occurred and relief of composite symptoms after 7 days treatment.FINDINGS: All 408 participants were followed up to meet clinical endpoint and included in statistical analysis. The baseline characteristics were comparable between 2 groups. The number of worsening patients in the CHM group was 5 (2.5%), and that in the control group was 16 (7.8%). There was a significant difference between groups (P=0.014). 8 foreseeable mild adverse events occurred without statistical difference between groups.INTERPRETATION: 7-day early treatment with Huashibaidu granule reduced worsening conversion of mild COVID-19 patients. Our study supports Huashibaidu Granule as an active option for early treatment of mild COVID-19 in similar medical locations with well management.TRIAL REGISTRATION: The Chinese Clinical Trial Registry: ChiCTR2000029763.FUNDING: This study was supported by “National Key R&D Program of China” (No.2020YFC0841500).DECLARATION OF INTERESTS: The authors guaranteed that there existed no competing interest in this paper.ETHICS APPROVAL STATEMENT: Ethics Review Committee of Institute of Basic Research in Clinical Medicine, China Academy of Chinese Medical Sciences Approval of Ethical Review Acceptance Number: S2020-001; Approval Number: P20001/PJ01.

Invisible Agents of COVID-19 Transmission? Common Sources, Characteristics, and Implications of Indoor Aerosols (preprint)

The positive association between outdoor atmospheric particulate matter and the morbidity and mortality of Coronavirus Disease 2019 (COVID-19) infections was concluded by recent studies. Since people spend most of their time indoor, aerosol particles generated by indoor activities have inherently closer links to human occupants and more direct implications on the airborne transmission of COVID-19. In light of this risk, we reviewed the characteristics of aerosol particles emitted from common indoor sources and how exposure to those particles affects human respiratory infections as well as the transport of airborne pathogens. Activities such as tobacco smoking, cooking, vacuum cleaning, laser printing, and burning candles, mosquito coils or incenses can generate large quantities of particles, mostly in the ultrafine range (< 100 nm). These tiny particles – each may have unique properties and aerodynamics depending on the sources and environmental conditions upon their release – could stay airborne and deposit in the deeper regions of human airways while being difficult to clear by the respiratory system. Adverse effects can be induced by inhaled aerosol particles via oxidative stress and inflammation. Early epidemiology evidence and animal studies showed the confounding effects of particle exposure in respiratory infections. Specifically, inhaled particles can impair human respiratory systems and immune functions and induce the upregulation of angiotensin-converting enzyme 2, causing vulnerability to COVID-19 infection. Moreover, co-production of inflammation mediators by COVID-19 infection and particle exposure magnifies the cytokine storm and aggravates symptoms in patients. We also discuss the possibility of indoor aerosol particles being virus carriers in the airborne transmission of COVID-19. Although many hypotheses were proposed in recent discussions, no rigorous evidence was provided to elucidate interactions between aerosol articles and virus-laden droplets or droplet nuclei, and studies are needed on how these interactions affect the persistence, transport, and lung deposition of COVID-19 and other airborne pathogens.

Structural, Biophysical, and Biochemical Elucidation of the SARS-CoV-2 Nonstructural Protein 3 Macro Domain.

The pandemic outbreak of a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has threatened the global public health and economy since late December 2019. SARS-CoV-2 encodes the conserved macro domain within nonstructural protein 3, which may reverse cellular ADP-ribosylation and potentially cut the signal of a viral infection in the cell. Herein, we report that the SARS-CoV-2 macro domain was examined as a poly-ADP-ribose (ADPR) binding module and possessed mono-ADPR cleavage enzyme activity. After confirming the ADPR binding ability via a biophysical approach, the X-ray crystal structure of the SARS-CoV-2 macro domain was determined and structurally compared with those of other viruses. This study provides structural, biophysical, and biochemical bases to further evaluate the role of the SARS-CoV-2 macro domain in the host response via ADP-ribose binding but also as a potential target for drug design against COVID-19.

Disability Discrimination, Medical Rationing and COVID-19 (preprint)

The current public health crisis has exposed deep cracks in social equality and justice for marginalised and vulnerable communities around the world. The reported rise in the number of ‘do not resuscitate’ orders being imposed on people with disabilities has caused particular concerns from a human rights perspective. While the evidence of this is contested, this article will consider the human rights implications at stake and the dangers associated with using ‘quality of life’ measures as determinants of care in medical decision-making and triage assessments.

Safety and Feasibility of Umbilical Cord Mesenchymal Stem Cells in Patients with COVID-19 Pneumonia: A Pilot Study (preprint)

Background: We aim to explore the safety and feasibility of umbilical cord mesenchymal stem cells (UC-MSCs) transplantation in severe and critically severe type Coronavirus disease 2019 (COVID-19) patients.Methods: In addition to normal therapy, we performed four times transplantation of UC-MSCs in 16 severe and critically severe type COVID-19 patients. We observed adverse events from enrollment to D28. We evaluated the oxygenation index, inflammatory biomarkers, chest imaging, lymphocyte subsets count et al on the 7th day (D7±1 day), the 14th day (D14±1 day) and the 28th day (D28±3 days).Results: There were no infusion-related or allergic reactions. The oxygenation index was improved after transplantation. The mortality of enrolled patients was 6.25%. The level of cytokines estimated was varied in normal range, the chest imaging was improved, the lymphocyte count and lymphocyte subsets count were recovered after transplantation.Conclusions: Intravenous transplantation of UC-MSCs was safe and feasible for treatment in patients with COVID-19 pneumonia.Trial registration: Clinical Trial, NCT04269525. Registered 7 February 2020. https://clinicaltrials.gov/ct2/show/NCT04269525