SARS-CoV-2 bivalent mRNA vaccine with broad protection against variants of concern.

Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has rapidly spread around the globe. With a substantial number of mutations in its Spike protein, the SARS-CoV-2 Omicron variant is prone to immune evasion and led to the reduced efficacy of approved vaccines. Thus, emerging variants have brought new challenges to the prevention of COVID-19 and updated vaccines are urgently needed to provide better protection against the Omicron variant or other highly mutated variants. Materials and methods: Here, we developed a novel bivalent mRNA vaccine, RBMRNA-405, comprising a 1:1 mix of mRNAs encoding both Delta-derived and Omicron-derived Spike proteins. We evaluated the immunogenicity of RBMRNA-405 in BALB/c mice and compared the antibody response and prophylactic efficacy induced by monovalent Delta or Omicron-specific vaccine with the bivalent RBMRNA-405 vaccine in the SARSCoV-2 variant challenge. Results: Results showed that the RBMRNA-405 vaccine could generate broader neutralizing antibody responses against both Wuhan-Hu-1 and other SARS-CoV-2 variants, including Delta, Omicron, Alpha, Beta, and Gamma. RBMRNA-405 efficiently blocked infectious viral replication and lung injury in both Omicron- and Delta-challenged K18-ACE2 mice. Conclusion: Our data suggest that RBMRNA-405 is a promising bivalent SARS-CoV-2 vaccine with broad-spectrum efficacy for further clinical development.

Occupational Risk Factors for Physical and Mental Health in Primary Healthcare Providers: A National Cross-Sectional Survey from 62 Urban Communities in China.

Purpose: To understand the physical and mental health status of primary healthcare providers (PHPs) including physicians, nurses and other staff and the workplace risk factors for depression, anxiety and intention-to-leave. Patients and Methods: In December 2021, a national cross-sectional survey was conducted from 62 urban communities in China, and all PHPs were invited to complete a standardized questionnaire. Information on demographic, health-related lifestyle, cardiovascular risk factors and physical health status, occupational stress and intention-to-leave was collected. Depression and anxiety were assessed using the Zung Self-Rating Anxiety/Depression Scale (SAS/SDS). Results: A total of 4901 PHPs were included. 67.0% males currently drank alcohol vs 25.3% in females; 36.0% males currently smoked cigarettes vs 1.4% in females. Notably, more than half males were overweight or obese, but this proportion was 24.2% in females. The prevalence of chronic diseases, including hypertension, diabetes, dyslipidemia, non-alcoholic fatty liver disease, gout, and disease clustering were higher in males than in females. The prevalence of depression and anxiety were high, 50% had depression, of whom 15.6% had moderate/severe depression. Over 15% participants had varied levels of anxiety, and approximately 4% had moderate/severe anxiety. PHPs who aged 18-29 (OR: 1.31, 95% CI: 1.05-1.64), were males (OR: 1.34, 95% CI: 1.14-1.57), with lower professional title (comparing with staff with senior title, the ORs of the intermedium, junior and none were 1.83, 2.18 and 2.49, respectively), took charge in nursing (OR: 1.41, 95% CI: 1.20-1.65), with higher perceived stress level (OR: 1.82, 95% CI: 1.41-2.34), and suffering from severe fatigue (OR: 2.55, 95% CI: 1.99-3.27) were more likely to have depression. Likewise, PHPs who were younger, with intermedium professional title, had higher perceived pressure level, and higher fatigue levels were more likely to have anxiety. Conclusion: The mental health of PHPs is worrisome, with a high burden of chronic diseases and occupational risk factors. Younger PHPs, nurses, and those with higher levels of work pressure and fatigue are more vulnerable to psychological problems. The high prevalence of intention-to-leave calls for strategies that relieve the workplace stress and enhance the human resource capability.

Chemical Control of CRISPR Gene Editing via Conditional Diacylation Crosslinking of Guide RNAs.

Conditional control of RNA structure and function has emerged as an effective toolkit. Here, a strategy based on a one-step introduction of diacylation linkers and azide groups on the 2'-OH of RNA is advance. Selected from eight phosphine reagents, it is found that 2-(diphenylphosphino)ethylamine has excellent performance in reducing azides via a Staudinger reduction to obtain the original RNA. It is demonstrated that the enzymatic activities of Cas13 and Cas9 can be regulated by chemically modified guide RNAs, and further achieved ligand-induced gene editing in living cells by a controllable CRISPR/Cas9 system.

Efficacy and safety of auto-cross-linked hyaluronic gel to prevent intrauterine adhesion after hysteroscopic electrosurgical resection: a multi-center randomized controlled trial.

Background: The electrothermal effect of hysteroscopic bipolar electrosurgical resection may cause damage to the endometrium, leading to intrauterine adhesion (IUA). Although some studies have demonstrated the efficacy and feasibility of auto-cross-linked hyaluronic (ACP) gel in preventing IUAs, controversy over its use continues. In this randomized controlled multi-center 2-arm parallel trial, we aimed to examine the efficacy and safety of ACP gel in preventing IUA after hysteroscopic electrosurgical resection and facilitate pregnancy in patients. Methods: Patients from 4 centers in China were randomly assigned (1:1) to receive an intrauterine infusion of ACP gel or nothing after hysteroscopic electrosurgical resection. The randomization assignment was generated by computer and kept in a sealed envelope. A second-look hysteroscopy was performed within 3 months of the surgery. Results: From June 2018 to May 2021, 200 patients were recruited. Ultimately, 82 patients in both groups were included in the result analysis. The baseline characteristics were comparable. The outcomes were assessed by using per-protocol analysis. The incidence of IUA in the ACP gel group was lower than that in the control group [3.66% vs. 10.98%, risk ratio (RR) =0.333, 95% confidence interval (CI): 0.094-1.187, P=0.072], and the planned pregnancy rate was higher than that of the control group (60.98% vs. 40.54%, RR =1.504, 95% CI: 0.949-2.384, P=0.071), but the difference was not statistically significant. There was no significant difference in menstruation change. Menstrual volume remained unchanged in most cases (86.59% in ACP gel group vs. 89.02% in the control group, RR =0.877, 95% CI: 0.877-1.109, P=0.815). Menstrual volume decreased in 10 women in the ACP gel group and 8 in the control group (12.20% vs. 9.76%, RR =1.250, 95% CI: 0.520-3.007, P=0.617). No adverse effects were observed after the ACP administration. Conclusions: The present study showed that the use of ACP gel appeared to reduce both the tendency of IUA and American Fertility Society (AFS) scores and improve the subsequent pregnancy rate during hysteroscopic electrosurgical resection when treating polyps, fibroids, and uterine septum. ACP might be recommended to prevent IUA after such surgery. Further studies should be conducted with larger numbers of participants. Trial Registration: Chinese Clinical Trial Registry ChiCTR2100047165.

Exploration of the impact of political ideology disparity on COVID-19 transmission in the United States.

BACKGROUND: Based on individual-level studies, previous literature suggested that conservatives and liberals in the United States had different perceptions and behaviors when facing the COVID-19 threat. From a state-level perspective, this study further explored the impact of personal political ideology disparity on COVID-19 transmission before and after the emergence of Omicron. METHODS: A new index was established, which depended on the daily cumulative number of confirmed cases in each state and the corresponding population size. Then, by using the 2020 United States presidential election results, the values of the built index were further divided into two groups concerning the political party affiliation of the winner in each state. In addition, each group was further separated into two parts, corresponding to the time before and after Omicron predominated. Three methods, i.e., functional principal component analysis, functional analysis of variance, and function-on-scalar linear regression, were implemented to statistically analyze and quantify the impact. RESULTS: Findings reveal that the disparity of personal political ideology has caused a significant discrepancy in the COVID-19 crisis in the United States. Specifically, the findings show that at the very early stage before the emergence of Omicron, Democratic-leaning states suffered from a much greater severity of the COVID-19 threat but, after July 2020, the severity of COVID-19 transmission in Republican-leaning states was much higher than that in Democratic-leaning states. Situations were reversed when the Omicron predominated. Most of the time, states with Democrat preferences were more vulnerable to the threat of COVID-19 than those with Republican preferences, even though the differences decreased over time. CONCLUSIONS: The individual-level disparity of political ideology has impacted the nationwide COVID-19 transmission and such findings are meaningful for the government and policymakers when taking action against the COVID-19 crisis in the United States.

Engineering SARS-CoV-2 specific cocktail antibodies into a bispecific format improves neutralizing potency and breadth.

One major limitation of neutralizing antibody-based COVID-19 therapy is the requirement of costly cocktails to reduce emergence of antibody resistance. Here we engineer two bispecific antibodies (bsAbs) using distinct designs and compared them with parental antibodies and their cocktail. Single molecules of both bsAbs block the two epitopes targeted by parental antibodies on the receptor-binding domain (RBD). However, bsAb with the IgG-(scFv)2 design (14-H-06) but not the CrossMAb design (14-crs-06) shows increased antigen-binding and virus-neutralizing activities against multiple SARS-CoV-2 variants as well as increased breadth of neutralizing activity compared to the cocktail. X-ray crystallography and cryo-EM reveal distinct binding models for individual cocktail antibodies, and computational simulations suggest higher inter-spike crosslinking potentials by 14-H-06 than 14-crs-06. In mouse models of infections by SARS-CoV-2 and multiple variants, 14-H-06 exhibits higher or equivalent therapeutic efficacy than the cocktail. Rationally engineered bsAbs represent a cost-effective alternative to antibody cocktails and a promising strategy to improve potency and breadth.

3D printing of nanowrinkled architectures via laser direct assembly.

Structural wrinkles in nature have been widely imitated to enhance the surface functionalities of objects, especially three-dimensional (3D) architectured wrinkles, holding promise for emerging applications in mechanical, electrical, and biological processes. However, the fabrication of user-defined 3D nanowrinkled architectures is a long-pending challenge. Here, we propose a bottom-up laser direct assembly strategy to fabricate multidimensional nanowrinkled architectures in a single-material one-step process. Through the introduction of laser-induced thermal transition into a 3D nanoprinting process for leading the point-by-point nanoscale wrinkling and the self-organization of wrinkle structures, we have demonstrated the program-controlled and on-demand fabrication of multidimensional nanowrinkled structures. Moreover, the precise control of wrinkle morphology with an optimal wavelength of 40 nanometers and the regulation of the dynamic transformation of wrinkled cellular microstructures via interfacial stress mismatch engineering have been achieved. This study provides a universal protocol for constructing nearly arbitrary nanowrinkled architectures and facilitates a new paradigm in nanostructure manufacturing.

"Flipped" clinical rotations: A novel approach.

BACKGROUND: Near the beginning of the COVID-19 pandemic in the United States, medical students were pulled out of all in-person patient care activities. This resulted in massive disruption to the required clinical rotations (clerkships), necessitating creative curricular solutions to ensure continued education for medical students. APPROACH: In response to the lockout, our school adopted a "flipped" clinical rotations model that assigned students to remote learning activities prior to in-person patient care activities. This approach allowed students to continue their clinical education virtually with a focus on knowledge for practice while awaiting return to the shortened in-person portions of their rotation. In planning the modified clinical curriculum, educational leaders adhered to several guiding principles including ensuring flexible remote curricular components that would engage students in active learning, designating that no rotation would be completely virtual, and completing virtual educational activities and standardised exams before students returned to in-person experiences. EVALUATION: End of rotation evaluations and standardised exam scores were analysed to determine the effectiveness of this model. Despite the disruption associated with the pandemic and the rapid implementation of the "flipped" rotations, students continued to rate the overall experiences as highly as traditional clinical rotations. Students also performed similarly on standardised exams when compared to cohorts from other classes at the same experience level. IMPLICATIONS: While borne out of necessity during a pandemic, the lessons learned from our implementation of a "flipped" rotations model can be applied to address problems of capacity and clinical preparedness in the clinical setting.

Clinical efficacy and mechanism of mesenchymal stromal cells in treatment of COVID-19.

Coronavirus disease 2019 (COVID-19) is a highly infectious epidemic disease that has seriously affected human health worldwide. To date, however, there is still no definitive drug for the treatment of COVID-19. Cell-based therapies could represent a new breakthrough. Over the past several decades, mesenchymal stromal cells (MSCs) have proven to be ideal candidates for the treatment of many viral infectious diseases due to their immunomodulatory and tissue repair or regeneration promoting properties, and several relevant clinical trials for the treatment of COVID-19 have been registered internationally. Herein, we systematically summarize the clinical efficacy of MSCs in the treatment of COVID-19 based on published results, including mortality, time to symptom improvement, computed tomography (CT) imaging, cytokines, and safety, while elaborating on the possible mechanisms underpinning the effects of MSCs, to provide a reference for subsequent studies.

The Abnormal Imaging of SARS-CoV-2: A Predictive Measure of Disease Severity.

To investigate the characteristics of SARS-CoV-2 pneumonia and evaluate whether CT scans, especially at a certain CT level, could be used to predict the severity of SARS-CoV-2 pneumonia. In total 118 confirmed patients had been enrolled. All data including epidemiological, clinical characteristics, laboratory results, and images were collected and analyzed when they were administrated for the first time. All patients were divided into two groups. There were 106 severe/critical patients and 12 common ones. A total of 38 of the patients were women. The mean age was 50.5 ± 11.5 years. Overall, 80 patients had a history of exposure. The median time from onset of symptoms to administration was 8.0 days. The main symptoms included fever, cough, anorexia, fatigue, myalgia, headaches, and chills. Lymphocytes and platelets decreased and lactate dehydrogenase increased with increased diseased severity (P < 0.05). Calcium and chloride ions were decreased more significantly in severe/critical patients than in common ones (P < 0.05). The main comorbidities were diabetes, chronic cardiovascular disease, and chronic pulmonary disease, which occurred in 47 patients. In all 69 patients had respiratory failure, which is the most common SARS-CoV-2 complication, and liver dysfunction presented in 37 patients. Nine patients received mechanical ventilation therapy. One patient received continuous blood purification and extracorporeal membrane oxygenation (EMCO) treatments. The average stay was 18.1 ± 10.8 days. Four patients died. The median of the radiographic score was four in common, and five in the severe/critical illness, which was a significant difference between the two groups. The radiographic score was in negative correlation with OI (ρ = -0.467, P < 0.01). The OI in severe/critically ill cases decreased significantly as the disease progressed, which was related to the lesion area in the left lung and right lungs (ρ = 0.688, R = 0.733). OI, the lesion area in the left lung and right lungs, lymphocytes, etc. were associated with different degrees of SARS-CoV-2 pneumonia (P < 0.05). The lesion area in both lungs were possible predictive factors for severe/critical cases. Patients with SARS-CoV-2 pneumonia showed obvious clinical manifestations and laboratory result changes. Combining clinical features and the quantity of the lesion area in the fourth level of CT could effectively predict severe/critical SARS-CoV-2 cases.

Inpatient use of metformin and acarbose is associated with reduced mortality of COVID-19 patients with type 2 diabetes mellitus.

AIMS: Type 2 diabetes mellitus (T2DM) is a strong risk factor for complications of coronavirus disease 2019 (COVID-19). The effect of T2DM medications on COVID-19 outcomes remains unclear. In a retrospective analysis of a cohort of 131 patients with T2DM hospitalized for COVID-19 in Wuhan, we have previously found that metformin use prior to hospitalization is associated with reduced mortality. The current study aims to investigate the effects of inpatient use of T2DM medications, including metformin, acarbose, insulin and sulfonylureas, on the mortality of COVID-19 patients with T2DM during hospitalization. METHODS: We continue to carry out a retrospective analysis of a cohort of 131 patients with T2DM hospitalized for COVID-19 and treated with different combinations of diabetes medications. RESULTS: We found that patients using metformin (p = .02) and acarbose (p = .04), alone or both together (p = .03), after admission were significantly more likely to survive than those who did not use either metformin or acarbose. 37 patients continued to take metformin after admission and 35 (94.6%) survived. Among the 57 patients who used acarbose after admission, 52 survived (91.2%). A total of 20 patients used both metformin and acarbose, while 57 used neither. Of the 20 dual-use patients, 19 (95.0%) survived. CONCLUSION: Our analyses suggest that inpatient use of metformin and acarbose together or alone during hospitalization should be studied in randomized trials.

‘We Are Children of God’: An Ethnography of a Catholic Community in Rural China in the COVID-19 Pandemic

Academic studies of the relationship between religion and pandemics have been emerging since the beginning of the COVID-19 pandemic. However, many of these studies have been conducted in Euro-American contexts, with little attention paid to non-Western cases. This article provides a local case study from China, the earliest epicenter of the pandemic. The study focused on a Catholic community in rural China, Little Rome, through the lens of lived religion, exploring the relationship between religion and the COVID-19 pandemic. Participants in our ethnographic study indicated that the Church plays an essential role in responding to the pandemic. In contrast to conventional studies of lived religion, in this ethnographic study on Catholicism in China, we contend that while the study of the lived experience of individuals is central to the lived-religion approach, more attention needs to be paid to the role of religious institutions such as the church, which mediate relations between individuals, society, and other social institutions. This article also argues that investigating different places and cultures can provide rich data for understanding the dynamic and diverse relationship between religion and the pandemic.

yIssuance Overpricing of China's Corporate Debt Securities

We document issuance overpricing of corporate debt securities in China, which is robust across subsamples with different credit ratings, maturities, and issuers. This phenomenon contrasts with underpricing of equity and debt securities in Western countries and reflects China's distinct institutional environment. The average overpricing dropped from 7.44 basis points to 2.41 basis points after the government prohibited underwriters from using rebates in issuances in October 2017. By analyzing overpricing before and after the rebate ban and across different issuers and underwriters, we uncover two channels for underwriters, who compete for future underwriting business, to drive up overpricing: rebates and self-purchases.

Nasal delivery of an IgM offers broad protection from SARS-CoV-2 variants.

Resistance represents a major challenge for antibody-based therapy for COVID-191-4. Here we engineered an immunoglobulin M (IgM) neutralizing antibody (IgM-14) to overcome the resistance encountered by immunoglobulin G (IgG)-based therapeutics. IgM-14 is over 230-fold more potent than its parental IgG-14 in neutralizing SARS-CoV-2. IgM-14 potently neutralizes the resistant virus raised by its corresponding IgG-14, three variants of concern-B.1.1.7 (Alpha, which first emerged in the UK), P.1 (Gamma, which first emerged in Brazil) and B.1.351 (Beta, which first emerged in South Africa)-and 21 other receptor-binding domain mutants, many of which are resistant to the IgG antibodies that have been authorized for emergency use. Although engineering IgG into IgM enhances antibody potency in general, selection of an optimal epitope is critical for identifying the most effective IgM that can overcome resistance. In mice, a single intranasal dose of IgM-14 at 0.044 mg per kg body weight confers prophylactic efficacy and a single dose at 0.4 mg per kg confers therapeutic efficacy against SARS-CoV-2. IgM-14, but not IgG-14, also confers potent therapeutic protection against the P.1 and B.1.351 variants. IgM-14 exhibits desirable pharmacokinetics and safety profiles when administered intranasally in rodents. Our results show that intranasal administration of an engineered IgM can improve efficacy, reduce resistance and simplify the prophylactic and therapeutic treatment of COVID-19.

Metformin Use in Diabetes Prior to Hospitalization: Effects on Mortality in Covid-19.

OBJECTIVE: Although type 2 diabetes mellitus (T2DM) has been reported as a risk factor for coronavirus disease 2019 (COVID-19), the effect of pharmacologic agents used to treat T2DM, such as metformin, on COVID-19 outcomes remains unclear. Metformin increases the expression of angiotensin converting enzyme 2, a known receptor for severe acute respiratory syndrome coronavirus 2. Data from people with T2DM hospitalized for COVID-19 were used to test the hypothesis that metformin use is associated with improved survival in this population. METHODS: Retrospective analyses were performed on de-identified clinical data from a major hospital in Wuhan, China, that included patients with T2DM hospitalized for COVID-19 during the recent epidemic. One hundred and thirty-one patients diagnosed with COVID-19 and T2DM were used in this study. The primary outcome was mortality. Demographic, clinical characteristics, laboratory data, diabetes medications, and respiratory therapy data were also included in the analysis. RESULTS: Of these 131 patients, 37 used metformin with or without other antidiabetes medications. Among the 37 metformin-taking patients, 35 (94.6%) survived and 2 (5.4%) did not survive. The mortality rates in the metformin-taking group versus the non-metformin group were 5.4% (2/37) versus 22.3% (21/94). Using multivariate analysis, metformin was found to be an independent predictor of survival in this cohort (P = .02). CONCLUSION: This study reveals a significant association between metformin use and survival in people with T2DM diagnosed with COVID-19. These clinical data are consistent with potential benefits of the use of metformin for COVID-19 patients with T2DM.

Respiratory tract samples collected from patients in a region of Quebec, Canada, indicate the absence of early circulation of SARS-CoV-2 infection.

Background: The first documented case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Quebec was confirmed on February 27, 2020. Retracing the first cases that occur within a geographical region may provide insight regarding the evolution and spread of SARS-CoV-2 in that region because the spread of undiagnosed cases may facilitate the initial community amplification of the virus. Methods: We performed a retrospective analysis of respiratory tract samples collected for influenza testing in a region of Quebec, Canada, to look for evidence of early circulation of SARS-CoV-2. Frozen nucleic acid extracts initially collected for influenza testing between January 1 and February 20, 2020, were tested for SARS-CoV-2 using a reverse transcription-polymerase chain reaction assay. Results: During the study period, 1,440 of 2,121 (67.9%) nucleic acid extracts from individual patients were available for retrospective testing. None of the samples tested positive for SARS-CoV-2. Conclusions: The results suggest that SARS-CoV-2 was not circulating within the region before February 20, 2020, because many samples, representing more than two-thirds of all samples tested for influenza during early 2020, were tested. Further studies using a similar methodology to determine the date of onset of SARS-CoV-2 in different countries and geographic areas could enhance our understanding of the current pandemic.

Historique: Le premier cas démontré d'infection par le syndrome respiratoire aigu sévère à coronavirus 2 (SARS-CoV-2) au Québec a été confirmé le 27 février 2020. Le retraçage du premier cas survenu dans une région géographique peut donner un aperçu de l'évolution et de la propagation du virus SARS-CoV-2 dans cette région, car la transmission des cas non diagnostiqués peut favoriser l'amplification initiale du virus dans la communauté. Méthodologie: Les chercheurs ont procédé à l'analyse rétrospective des échantillons respiratoires prélevés pour le dépistage de la grippe dans une région du Québec, au Canada, afin de trouver des preuves de circulation précoce du virus SARS-CoV-2D. Les extraits d'acide nucléique congelés entre le 1er janvier et le 20 février 2020 ont été soumis au dépistage du virus SARS-CoV-2 au moyen de l'amplification en chaîne par polymérase après transcriptase inverse. Résultats: Pendant la période de l'étude, 1 440 des 2 121 extraits d'acide nucléique (67,9 %) provenant de patients différents étaient disponibles en vue de tests rétrospectifs. Aucun n'a été positif au virus SARS-CoV-2. Conclusions: D'après les résultats, le virus SARS-CoV-2 n'était pas en circulation dans la région avant le 20 février 2020, car de nombreux échantillons, représentant plus des deux tiers de tous ceux ayant servi au dépistage de la grippe au début de l'année 2020, ont été soumis au dépistage. D'autres études faisant appel à une méthodologie semblable pour déterminer la date d'apparition du virus SARS-CoV-2 dans divers pays et diverses régions géographiques pourraient permettre de mieux comprendre la pandémie en cours.

Anosmie et dysgueusie associées à l'infection au SRAS-CoV-2: étude cas­témoins appariée selon l'âge.

CONTEXTE: On a signalé l'anosmie et la dysgueusie comme symptômes potentiels de la maladie à coronavirus 2019. Cette étude visait à confirmer si ces symptômes sont caractéristiques chez les personnes ayant eu un résultat positif au dépistage du coronavirus du syndrome respiratoire aigu sévère 2 (SRAS-CoV-2). MÉTHODES: Nous avons réalisé une étude cas­témoins appariée selon l'âge dans la région des Cantons-de-l'Est, au Québec, entre le 10 et le 23 mars 2020. Nous avons inclus les adultes (18 ans et plus) ayant obtenu un résultat positif au dépistage du SRAS-CoV-2 par test d'amplification en chaîne par polymérase couplée à une transcription inverse. Les cas ont été appariés (1:1) par tranche d'âge de 5 ans avec des témoins sélectionnés aléatoirement parmi tous les patients ayant eu un résultat négatif au dépistage pendant la même période. Les données démographiques et de laboratoire ont été récupérées dans les dossiers médicaux. Les symptômes cliniques et les comorbidités associés à l'anosmie et à la dysgueusie ont été notés lors d'entrevues téléphoniques faites au moyen d'un questionnaire standardisé. RÉSULTATS: Parmi les 2883 personnes soumises au dépistage du SRAS-CoV-2, nous avons recensé 134 cas positifs (70 femmes [52,2 %] et 64 hommes [47,8 %]; âge médian 57,1 ans [intervalle interquartile 41,2­64,5 ans]). Les symptômes indépendamment associés à l'infection confirmée au SRAS-CoV-2 dans une analyse de régression logistique conditionnelle étaient les suivants : anosmie et/ou dysgueusie (rapport de cotes [RC] ajusté 62,9; intervalle de confiance [IC] de 95 % 11,0­359,7), myalgie (RC ajusté 7,6; IC de 95 % 1,9­29,9), vision trouble (RC ajusté 0,1; IC de 95 % 0,0­0,8) et douleur thoracique (RC ajusté 0,1; IC de 95 % 0,0­0,6). INTERPRÉTATION: Nous avons observé un lien étroit entre les symptômes olfactifs et gustatifs et la positivité au SRAS-CoV-2. Ces symptômes devraient être considérés comme une caractéristique fréquente et distinctive de l'infection au SRAS-CoV-2 et devraient servir d'indication de dépistage, et même de répétition du dépistage chez les personnes dont le résultat initial est négatif.

Clinical characteristics and viral shedding kinetics of 38 asymptomatic patients with coronavirus disease 2019: A retrospective observational study.

ABSTRACT: This study aims to investigate the clinical characteristics and viral shedding kinetics of asymptomatic patients with coronavirus disease 2019 (COVID-19).The data of 38 asymptomatic patients positive for SARS-CoV-2 nucleic acid were collected from February to March 2020 in Tuanfeng County, Huanggang, Hubei, China. The epidemiology, laboratory examination, chest imaging, viral nucleic acid test results, clinical characteristics, and viral shedding time were summarized in this retrospective study.The study included 20 family members of patients with COVID-19, 10 medical personnel participating in COVID-19 treatment or working in a fever clinic, 6 personnel from quarantine places, 1 individual with a close contact history with confirmed patients, and 1 local epidemic prevention personnel. All were positive for SARS-CoV-2 nucleic acid. The white blood cell (WBC) count, the absolute value of lymphocytes, C-reactive protein (CRP), and D-dimer were normal. Pneumonia manifestations were not found in the chest computed tomography (CT) scan of 36 patients; the remaining 2 cases included a 1-year-old child and a pregnant woman, and they did not undergo chest CT. The viral shedding time was 6 days.All asymptomatic patients with COVID-19 had a history of close contact or exposure. Laboratory tests were normal. Chest imaging did not show any pneumonia manifestation. The viral shedding time was <10 days, which is shorter than that of patients with COVID-19. A timely discovery of such asymptomatic infections is crucial for blocking the spread of the virus and strengthening the prevention and control measures.

A Novel Risk-Stratification Models of the High-Flow Nasal Cannula Therapy in COVID-19 Patients With Hypoxemic Respiratory Failure.

Background: High-flow nasal cannula (HFNC) has been recommended as a suitable choice for the management of coronavirus disease 2019 (COVID-19) patients with acute hypoxemic respiratory failure before mechanical ventilation (MV); however, delaying MV with HFNC therapy is still a dilemma between the technique and clinical management during the ongoing pandemic. Methods: Retrospective analysis of COVID-19 patients treated with HFNC therapy from four hospitals of Wuhan, China. Demographic information and clinical variables before, at, and shortly after HFNC initiation were collected and analyzed. A risk-stratification model of HFNC failure (the need for MV) was developed with the 324 patients of Jin Yin-tan Hospital and validated its accuracy with 69 patients of other hospitals. Results: Among the training cohort, the median duration of HFNC therapy was 6 (range, 3-11), and 147 experienced HFNC failure within 7 days of HFNC initiation. Early predictors of HFNC failure on the basis of a multivariate regression analysis included age older than 60 years [odds ratio (OR), 1.93; 95% confidence interval (CI), 1.08-3.44; p = 0.027; 2 points], respiratory rate-oxygenation index (ROX) <5.31 (OR, 5.22; 95% CI, 2.96-9.20; p < 0.001; 5 points) within the first 4 h of HFNC initiation, platelets < 125 × 109/L (OR, 3.04; 95% CI, 1.46-6.35; p = 0.003; 3 points), and interleukin 6 (IL-6) >7.0 pg/mL (OR, 3.34; 95% CI, 1.79-6.23; p < 0.001; 3 points) at HFNC initiation. A weighted risk-stratification model of these predictors showed sensitivity of 80.3%, specificity of 71.2% and a better predictive ability than ROX index alone [area under the curve (AUC) = 0.807 vs. 0.779, p < 0.001]. Six points were used as a cutoff value for the risk of HFNC failure stratification. The HFNC success probability of patients in low-risk group (84.2%) was 9.84 times that in the high-risk group (34.8%). In the subsequent validation cohort, the AUC of the model was 0.815 (0.71-0.92). Conclusions: Aged patients with lower ROX index, thrombocytopenia, and elevated IL-6 values are at increased risk of HFNC failure. The risk-stratification models accurately predicted the HFNC failure and early stratified COVID-19 patients with HFNC therapy into relevant risk categories.

Challenges and response in the medical management of the orthopaedic department during the coronavirus disease 2019 pandemic: strategies in Wuhan, China.

PURPOSE: Currently, COVID-19 has rapidly spread around the globe, there are already many nosocomial infections in medical staff. The purpose of this study is to provide some medical management experience from the orthopaedics department of Tongji Hospital in Wuhan, China, to provide reference for orthopaedists. METHODS: This study is a summary of the orthopaedic medical management of Tongji Hospital. It systematically summarized the Chinese experience including orthopaedic outpatient and emergency department management, and orthopaedic surgery and preventive management during the pandemic. RESULTS: We described some challenges in the orthopaedic department during the epidemic and formulated a set of medical management procedures to find an balance between effective treatment and infection prevention. CONCLUSION: These experiences and strategies could help orthopedists to work safely and effectively, and prevent nosocomial infections during the global pandemic of COVID-19.