Federal learning edge network based sentiment analysis combating global COVID-19.

As one of the important research topics in the field of natural language processing, sentiment analysis aims to analyze web data related to COVID-19, e.g., supporting China government agencies combating COVID-19. There are popular sentiment analysis models based on deep learning techniques, but their performance is limited by the size and distribution of the dataset. In this study, we propose a model based on a federal learning framework with Bert and multi-scale convolutional neural network (Fed_BERT_MSCNN), which contains a Bidirectional Encoder Representations from Transformer modules and a multi-scale convolution layer. The federal learning framework contains a central server and local deep learning machines that train local datasets. Parameter communications were processed through edge networks. The weighted average of each participant's model parameters was communicated in the edge network for final utilization. The proposed federal network not only solves the problem of insufficient data, but also ensures the data privacy of the social platform during the training process and improve the communication efficiency. In the experiment, we used datasets of six social platforms, and used accuracy and F1-score as evaluation criteria to conduct comparative studies. The performance of the proposed Fed_BERT_MSCNN model was generally superior than the existing models in the literature.

Detection rate of SARS-CoV-2 RNA in relation to isolation time and environmental surface type

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) causes environmental contamination via respiratory droplets and persists on contaminants and environmental surfaces for anywhere from a few hours to 6 days. Therefore, it is particularly important to understand the transmission and containment of SARS-CoV-2 on the surface of objects within isolated environments. In this study, 356 environmental surface samples were collected and 79 tested positive, with the highest contamination rate (56.96%) in the wood category (bedside tables, wood floors, and walls). This study revealed differences in the detection rates of environmental surfaces in hospitalized and discharged rooms of patients with confirmed COVID-19 in 2 isolated settings (A: p = 0.001;B: p = 0.505) and suggested that environmental contamination may be an important route of virus transmission, providing a reference to guide the enhancement of ventilation, the use of hotel isolation model, the advocacy of cotton masks, and the effective suppression of virus transmission.

Immune and pathophysiologic profiling of antenatal coronavirus disease 2019 in the GIFT cohort: A Singaporean case-control study

COVID-19 can be severe in pregnant women, and have adverse consequences for the subsequent infant. We profiled the post-infectious immune responses in maternal and child blood as well as breast milk in terms of antibody and cytokine expression and performed histopathological studies on placentae obtained from mothers convalescent from antenatal COVID-19. Seventeen mother-child dyads (8 cases of antenatal COVID-19 and 9 healthy unrelated controls;34 individuals in total) were recruited to the Gestational Immunity For Transfer (GIFT) study. Maternal and infant blood, and breast milk samples were collected over the first year of life. All samples were analyzed for IgG and IgA against whole SARS-CoV-2 spike protein, the spike receptor-binding domain (RBD), and previously reported immunodominant epitopes, as well as cytokine levels. The placentae were examined microscopically. The study is registered at clinicaltrials.gov under the identifier NCT04802278. We found high levels of virus-specific IgG in convalescent mothers and similarly elevated titers in newborn children. Thus, antenatal SARS-CoV-2 infection led to high plasma titers of virus-specific antibodies in infants postnatally. However, this waned within 3–6 months of life. Virus neutralization by plasma was not uniformly achieved, and the presence of antibodies targeting known immunodominant epitopes did not assure neutralization. Virus-specific IgA levels were variable among convalescent individuals’ sera and breast milk. Antibody transfer ratios and the decay of transplacentally transferred virus-specific antibodies in neonatal circulation resembled that for other pathogens. Convalescent mothers showed signs of chronic inflammation marked by persistently elevated IL17RA levels in their blood. Four placentae presented signs of acute inflammation, particularly in the subchorionic region, marked by neutrophil infiltration even though > 50 days had elapsed between virus clearance and delivery. Administration of a single dose of BNT162b2 mRNA vaccine to mothers convalescent from antenatal COVID-19 increased virus-specific IgG and IgA titers in breast milk, highlighting the importance of receiving the vaccine even after natural infection with the added benefit of enhanced passive immunity.

Bayesian inference

Bayesian statistical methods have become more popular in different applications of scientific research over the past several decades. This is mainly due to the computing capacity of modern machines and the recent advances in Bayesian computational methodologies. In this chapter, we give a brief introduction to Bayesian analysis and discuss the difference between Bayesian and classical frequentist statistics. To illustrate Bayesian methodologies, a diagnostic COVID-19 test is used to present the basic principles of the Bayesian approach, prior distribution, likelihood function, and posterior distribution. As an application of the Bayesian methodologies, we introduce Bayesian linear regression and Gaussian process regression and their Bayesian inference framework.

A Survey of Dummy-Based Location Privacy Protection Techniques for Location-Based Services.

As smart devices and mobile positioning technologies improve, location-based services (LBS) have grown in popularity. The LBS environment provides considerable convenience to users, but it also poses a significant threat to their privacy. A large number of research works have emerged to protect users' privacy. Dummy-based location privacy protection solutions have been widely adopted for their simplicity and enhanced privacy protection results, but there are few reviews on dummy-based location privacy protection. Or, for existing works, some focus on aspects of cryptography, anonymity, or other comprehensive reviews that do not provide enough reviews on dummy-based privacy protection. In this paper, the authors provide a review of dummy-based location privacy protection techniques for location-based services. More specifically, the connection between the level of privacy protection, the quality of service, and the system overhead is summarized. The difference and connection between various location privacy protection techniques are also described. The dummy-based attack models are presented. Then, the algorithms for dummy location selection are analyzed and evaluated. Finally, we thoroughly evaluate different dummy location selection methods and arrive at a highly useful evaluation result. This result is valuable both to users and researchers who are studying this field.

Psychosocial Determinants of Hand Hygiene, Facemask Wearing, and Physical Distancing During the COVID-19 Pandemic: A Systematic Review and Meta-analysis.

BACKGROUND: Hand hygiene, facemask wearing, and physical distancing play a crucial role in the prevention of the COVID-19 pandemic. Identifying the key psychosocial determinants of these precautionary behaviors contributes to effective intervention and policymaking for COVID-19 and future pandemics. PURPOSE: This study aimed to systematically review and meta-analyze available evidence on psychosocial determinants of the general population's practice of three precautionary behaviors, based on the Risk, Attitudes, Norms, Abilities, and Self-regulation (RANAS) framework. METHODS: Literature was identified by searching seven databases and relevant review papers. Observational and experimental studies targeting the general population (≥18 years) published between January 2020 to September 2021 were included. Pooled effect sizes were calculated with the inverse-variance method using random-effects models. RESULTS: A total of 51 studies (64 samples) were included in the qualitative synthesis, of which 30 studies (42 samples) were included in the meta-analysis. RANAS-based constructs including knowledge, pros attitudes, and perceived norms were identified as significant determinants of all three behaviors in the meta-analysis. Perceived susceptibility and cons attitudes showed no significant associations with any behaviors. Perceived severity, perceived control, self-efficacy, and behavioral intention were significantly associated with one or two behaviors. Country (western vs. eastern hemispheres) significantly moderated the effects of certain risk and ability factors. CONCLUSIONS: More research is needed with respect to the intention-behavior relationship, self-regulatory and reflexive factors of precautionary behaviors, as well as the exploration of the potential moderating effect of sociodemographic factors.

Identifying the psychosocial factors affecting the practice of three precautionary behaviors (hand hygiene, facemask wearing, and physical distancing) contributes to effective intervention and policymaking for the COVID-19 and future pandemics. Given the lack of summarized evidence, we conducted a systematic review and meta-analysis. Through seven databases and relevant review papers, we summarized the research findings of 51 observational studies that targeted the general population (≥18 years) and were published between January 2020 and September 2021. We found that (a) more knowledge, positive behavioral attitudes, and better compliance with the norms were associated with better practices of all three precautionary behaviors; (b) perceived susceptibility to the disease and negative behavioral attitudes were not associated with any precautionary behaviors; (c) higher levels of perceived disease severity, perceived behavioral control, self-efficacy, and behavioral intention were associated with better practices of one or two behaviors. In addition, we found that country (western vs. eastern hemispheres) differed in the relationship between psychosocial factors and behavioral practices. Specifically, both the association of perceived susceptibility with hand hygiene and the association of perceived severity with physical distancing were stronger among western populations. In contrast, the contribution of self-efficacy on the practice of physical distancing was stronger among eastern populations.

Occurrence and risk assessment of triclosan in freshwater lakes in the middle Yangtze River basin (Wuhan, Central China)

Triclosan (TCS) is an endocrine disrupting chemical which is commonly used as a disinfectant in pharmaceuticals and personal care products (PPCP's). Since early 2020, the worldwide outbreak of COVID-19 has increased the use of PPCP's, so the occurrence and impact of TCS on freshwater lakes should be considered. However, little attention has been given to the effect of TCS on freshwater lakes in China. This study is the first attempt at a risk assessment focusing on the temporal and spatial occurrence of TCS in freshwater lakes in the middle Yangtze River basin. The surface water and sediments of Donghu Lake and Liangzi Lake (Wuhan, Central China) were collected from October 2020 to August 2021. The maximum concentrations of TCS were 466 ng/L and 239 ng/L in surface water, 71 ng/g and 25 ng/g (dry weight) in sediments of Donghu Lake and Liangzi Lake, respectively. Significant temporal and spatial differences of TCS were observed within and between the lakes, with the highest concentrations measured in winter. Furthermore, higher concentrations of TCS were observed in areas that are more impacted by human activities. There was a significant positive correlation between TCS and nitrogen in the surface water. A risk assessment using the risk quotient (RQ) method showed that a potentially high risk (RQ > 1) was found only in surface waters from Donghu Lake, and that the sediments posed a lower risk than the surface waters. These results provide timely data on the temporal and spatial occurrence of TCS in freshwater lakes in China following the outbreak of COVID-19 and demonstrate a possible high risk of exposure to TCS for aquatic biota.

Proteomic and Metabolomic Characterization of SARS-CoV-2-Infected Cynomolgus Macaque at Early Stage

Although tremendous effort has been exerted to elucidate the pathogenesis of severe COVID-19 cases, the detailed mechanism of moderate cases, which accounts for 90% of all patients, remains unclear yet, partly limited by lacking the biopsy tissues. Here, we established the COVID-19 infection model in cynomolgus macaques (CMs), monitored the clinical and pathological features, and analyzed underlying pathogenic mechanisms at early infection stage by performing proteomic and metabolomic profiling of lung tissues and sera samples from COVID-19 CMs models. Our data demonstrated that innate immune response, neutrophile and platelet activation were mainly dysregulated in COVID-19 CMs. The symptom of neutrophilia, lymphopenia and massive “cytokines storm”, main features of severe COVID-19 patients, were greatly weakened in most of the challenged CMs, which are more semblable as moderate patients. Thus, COVID-19 model in CMs is rational to understand the pathogenesis of moderate COVID-19 and may be a candidate model to assess the safety and efficacy of therapeutics and vaccines against SARS-CoV-2 infection.

Association of Social-Cognitive Factors with Individual Preventive Behaviors of COVID-19 among a Mixed-Sample of Older Adults from China and Germany.

Identifying modifiable correlates of older adults' preventive behaviors is contributable to the prevention of the COVID-19 and future pandemics. This study aimed to examine the associations of social-cognitive factors (motivational and volitional factors) with three preventive behaviors (hand washing, facemask wearing, and physical distancing) in a mixed sample of older adults from China and Germany and to evaluate the moderating effects of countries. A total of 578 older adults (356 Chinese and 222 German) completed the online cross-sectional study. The questionnaire included demographics, three preventive behaviors before and during the pandemic, motivational factors (health knowledge, attitude, subjective norm, risk perception, motivational self-efficacy (MSE), intention), and volitional factors (volitional self-efficacy (VSE), planning, and self-monitoring) of preventive behaviors. Results showed that most social-cognitive factors were associated with three behaviors with small-to-moderate effect sizes (f2 = 0.02 to 0.17), controlled for demographics and past behaviors. Country moderated five associations, including VSE and hand washing, self-monitoring and facemask wearing, MSE and physical distancing, VSE and physical distancing, and planning and physical distancing. Findings underline the generic importance of modifiable factors and give new insights to future intervention and policymaking. Country-related mechanisms should be considered when aiming to learn from other countries about the promotion of preventive behaviors.

The Potential Complementary Role of Using Chinese Herbal Medicine with Western Medicine in Treating COVID-19 Patients: Pharmacology Network Analysis.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic in 2019-coronavirus disease (COVID-19). More and more Western medicine (WM) and Chinese herbal medicine (CHM) treatments have been used to treat COVID-19 patients, especially among Asian populations. However, the interactions between WM and CHM have not been studied. This study aims at using the network pharmacology approach to explore the potential complementary effects among commonly used CHM and WM in a clinical setting from a biomolecular perspective. Three well-published and widely used CHM formulas (National Research Institute of Chinese Medicine 101 (NRICM101), Qing-Fei-Pai-Du-Tang (QFPDT), Hua-Shi-Bai-Du-Formula (HSBDF)) and six categories of WM (Dexamethasone, Janus kinase inhibitors (JAKi), Anti-Interleukin-6 (Anti-IL6), anticoagulants, non-vitamin K antagonist oral anticoagulants (NOAC), and Aspirin) were included in the network pharmacology analysis. The target proteins on which these CHM and WM had direct effects were acquired from the STITCH database, and the potential molecular pathways were found in the REACTOME database. The COVID-19-related target proteins were obtained from the TTD database. For the three CHM formulas, QFPDT covered the most proteins (714), and 27 of them were COVID-19-related, while HSBDF and NRICM101 covered 624 (24 COVID-19-related) and 568 (25 COVID-19-related) proteins, respectively. On the other hand, WM covered COVID-19-related proteins more precisely and seemed different from CHM. The network pharmacology showed CHM formulas affected several inflammation-related proteins for COVID-19, including IL-10, TNF-α, IL-6, TLR3, and IL-8, in which Dexamethasone and Aspirin covered only IL-10 and TNF-α. JAK and IL-6 receptors were only inhibited by WM. The molecular pathways covered by CHM and WM also seemed mutually exclusive. WM had advantages in cytokine signaling, while CHM had an add-on effect on innate and adaptive immunity, including neutrophil regulation. WM and CHM could be used together to strengthen the anti-inflammation effects for COVID-19 from different pathways, and the combination of WM and CHM may achieve more promising results. These findings warrant further clinical studies about CHM and WM use for COVID-19 and other diseases.

Development and students' evaluation of a blended online and offline pedagogy for physical education theory curriculum in China during the COVID-19 pandemic.

The outbreak and continuation of the COVID-19 pandemic has challenged the implementation of physical education theory (PET) curriculums among global colleges and universities. This study aimed to describe the design and students' evaluation of a blended "Sports Multimedia Courseware Design" course among Chinese university students during the COVID-19 pandemic. Using information communication technologies, a 4-month blended course was developed, which consisted of 36 credits (18-credit online self-learning + 18-credit offline group-learning). A total of 1300 Chinese university students who majored in physical education, completed the blended course from Mar to Jun 2020, among which 238 (69.75% males; 21 ± 1.2 years) were randomly recruited to evaluate the course in terms of three aspects: (1) online self-learning, (2) offline group-learning, and (3) overall learning outcomes. A descriptive analysis was conducted using the IBM SPSS 27.0. Students' overall positive evaluation supported a successful development and implementation of the blended course. Over 90% of students fulfilled the learning tasks and satisfied with the online learning resources. About 83% of students indicated high levels of autonomous motivation and engagement in online self-learning. Approximately 88% of students showed positive attitudes to the offline group-learning content, while the participation rate (60%) was relatively lower than of the online self-learning. Over 50% of the students indicated self-improvements in diverse aspects after attending the blended course. Blended online and offline pedagogy shows apparent promise in delivering the PET course among Chinese university students during the COVID-19 pandemic. Further application and comprehensive evaluation are warranted in the future.

A systematic review and meta-analysis on the preventive behaviors in response to the COVID-19 pandemic among children and adolescents.

PURPOSE: The purpose of this review was to synthesize the empirical evidence of relevant studies related to preventive behaviors in response to the COVID-19 pandemic among children and adolescents. Further to this, we aimed to identify the demographic, psychological, and social and environmental correlates of such behaviors. METHODS: Following PRISMA guidelines, eligible literature was identified by searching seven databases (PsycINFO, PubMed, MEDLINE, EMBASE, Cochrane Library, PROSPERO registry platform, and ClinicalTrials.gov website) and reference list of included studies and relevant review papers from 1st Jan 2020 to 28th Feb 2021. The standardized mean difference and correlation coefficients r were extracted to estimate the effect sizes. Analyses were conducted using R software. RESULTS: Of the 35,271 original papers, 23 eligible studies were included in the qualitative synthesis and all these studies were of moderate-to-high quality, of which 17 studies were further included into the quantitative analysis. Children and adolescents (6-20 yrs.) showed a poorer practice of COVID-19 preventive behaviors compared to younger adults (21-59 yrs.) with a small-to-medium effect size (SMD = -.25, 95%CI = -.41 to -.09). For the demographic correlates, children and adolescents' COVID-19 preventive practice was found to be significantly associated with gender (r = .14, 95%CI = .10 to .18), while not with age (r = -.02, 95%CI = -.14 to .10). Narratively, knowledge was found to be consistently and significantly correlated. For the psychological correlates, small-to-medium overall effects were identified for the association with attitudes (r = .26, 95%CI = .21 to .31) and perceived severity (r = .16, 95%CI = .01 to .30). For the family and social correlates, a non-significant association was identified between family economic status and COVID-19 preventive behaviors (r = .004, 95%CI = -.12 to .12). CONCLUSIONS: Interventions and relevant policies of promoting children and adolescent's preventive measures should be a priority. Further, empirical studies identifying the demographic, psychological, and family and social correlates of children and adolescents' preventive behaviors are needed.

Association of Social-Cognitive Factors with Individual Preventive Behaviors of COVID-19 among a Mixed-Sample of Older Adults from China and Germany

Identifying modifiable correlates of older adults' preventive behaviors is contributable to the prevention of the COVID-19 and future pandemics. This study aimed to examine the associations of social-cognitive factors (motivational and volitional factors) with three preventive behaviors (hand washing, facemask wearing, and physical distancing) in a mixed sample of older adults from China and Germany and to evaluate the moderating effects of countries. A total of 578 older adults (356 Chinese and 222 German) completed the online cross-sectional study. The questionnaire included demographics, three preventive behaviors before and during the pandemic, motivational factors (health knowledge, attitude, subjective norm, risk perception, motivational self-efficacy (MSE), intention), and volitional factors (volitional self-efficacy (VSE), planning, and self-monitoring) of preventive behaviors. Results showed that most social-cognitive factors were associated with three behaviors with small-to-moderate effect sizes (f2 = 0.02 to 0.17), controlled for demographics and past behaviors. Country moderated five associations, including VSE and hand washing, self-monitoring and facemask wearing, MSE and physical distancing, VSE and physical distancing, and planning and physical distancing. Findings underline the generic importance of modifiable factors and give new insights to future intervention and policymaking. Country-related mechanisms should be considered when aiming to learn from other countries about the promotion of preventive behaviors.

Efficient empirical likelihood inference for recovery rate of COVID19 under double-censoring.

Doubly censored data are very common in epidemiology studies. Ignoring censorship in the analysis may lead to biased parameter estimation. In this paper, we highlight that the publicly available COVID19 data may involve high percentage of double-censoring and point out the importance of dealing with such missing information in order to achieve better forecasting results. Existing statistical methods for doubly censored data may suffer from the convergence problems of the EM algorithms or may not be good enough for small sample sizes. This paper develops a new empirical likelihood method to analyze the recovery rate of COVID19 based on a doubly censored dataset. The efficient influence function of the parameter of interest is used to define the empirical likelihood (EL) ratio. We prove that - 2 log (EL-ratio) asymptotically follows a standard χ 2 distribution. This new method does not require any scale parameter adjustment for the log-likelihood ratio and thus does not suffer from the convergence problems involved in traditional EM-type algorithms. Finite sample simulation results show that this method provides much less biased estimate than existing methods, when censoring percentage is large. The application to COVID19 data will help researchers in other field to achieve better estimates and forecasting results.

Immune and pathophysiologic profiling of antenatal COVID-19 in the GIFT cohort: A Singaporean case-control study. (preprint)

Background COVID-19 has been a major public health threat for the past two years, with disproportionate effects on the elderly, immunocompromised, and pregnant women. While much has been done in delineating immune dysfunctions and pathogenesis in the former two groups, less is known about the disease's progression in expectant women and children born to them. To address this knowledge gap, we profiled the immune responses in maternal and child sera as well as breast milk in terms of antibody and cytokine expression and performed histopathological studies on placentae obtained from mothers convalescent from antenatal COVID-19. Methods and findings A total of 17 mother-child dyads (8 cases of antenatal COVID-19 and 9 healthy unrelated controls; 34 individuals in total) were recruited to the Gestational Immunity For Transfer (GIFT) study. Maternal and infant sera, and breast milk samples were collected over the first year of life. All samples were analyzed for IgG and IgA against whole SARS-CoV-2 spike protein, the spike receptor-binding domain (RBD), and previously reported immunodominant epitopes, with conventional ELISA approaches. Cytokine levels were quantified in maternal sera using multiplex microbead-based Luminex arrays. The placentae were examined microscopically. We found high levels of virus-specific IgG in convalescent mothers and similarly elevated titers in newborn children. Virus-specific IgG in infant circulation waned within 3-6 months of life. Virus-specific IgA levels were variable among convalescent individuals' sera and breast milk. Convalescent mothers also showed a blood cytokine signature indicative of a persistent pro-inflammatory state. Four placentae presented signs of acute inflammation marked by neutrophil infiltration even though >50 days had elapsed between virus clearance and delivery. Administration of a single dose of BNT162b2 mRNA vaccine to mothers convalescent from antenatal COVID-19 increased virus-specific IgG and IgA titers in breast milk. Conclusions Antenatal SARS-CoV-2 infection led to high plasma titres of virus-specific antibodies in infants postnatally. However, this was not reflected in milk; milk-borne antibody levels varied widely. Additionally, placentae from COVID-19 positive mothers exhibited signs of acute inflammation with neutrophilic involvement, particularly in the subchorionic region. Virus neutralisation by plasma was not uniformly achieved, and the presence of antibodies targeting known immunodominant epitopes did not assure neutralisation. Antibody transfer ratios and the decay of transplacentally transferred virus-specific antibodies in neonatal circulation resembled that for other pathogens. Convalescent mothers showed signs of chronic inflammation marked by persistently elevated IL17RA levels in their blood. A single dose of the Pfizer BNT162b2 mRNA vaccine provided significant boosts to milk-borne virus-specific antibodies, highlighting the importance of receiving the vaccine even after natural infection with the added benefit of enhanced passive immunity. The study is registered at clinicaltrials.gov under the identifier NCT04802278.

The Short- and Long-Term Clinical, Radiological and Functional Consequences of COVID-19.

As with the rapid increase of the number of patients who have recovered from COVID-19 globally, there needs to be a major shift of the focus from rapid pathogen detection, treatment and prevention to the promotion of better recovery. Notwithstanding the scarcity of our understandings, recent studies have unraveled a plethora of pulmonary and systemic consequences which require medical attention. These consequences remained as of the end of follow-up which ranged from 1 month to 1 year. Here, we review the consequences of COVID-19 in terms of the residual symptoms, radiological and functional manifestations, and identify the potential risk factors that contribute to a prolonged recovery. We also summarize the benefits of clinical interventions (particularly the pulmonary rehabilitation program), and address several undetermined concerns and key future research directions.

Como consecuencia del rápido aumento del número de pacientes que se han recuperado de la COVID-19 en todo el mundo, es necesario cambiar el enfoque de la detección rápida del patógeno, el tratamiento y la prevención para promover una mejor recuperación. A pesar de la escasez de nuestros conocimientos, estudios recientes han desvelado una plétora de consecuencias pulmonares y sistémicas que requieren atención médica. Estas consecuencias se mantienen al final del seguimiento, que oscila entre 1 mes y 1 año. Aquí se hace una revisión de las consecuencias de la COVID-19 en términos de síntomas residuales y manifestaciones radiológicas y funcionales y se identifican los posibles factores de riesgo que contribuyen a una recuperación demorada. También se resumen los beneficios de las intervenciones clínicas (en particular el programa de rehabilitación pulmonar) y se abordan varias preocupaciones no resueltas y direcciones clave de investigación futura.

Individual Preventive Behaviors of COVID-19 and Associated Psychological Factors Among Chinese Older Adults: A Cross-Sectional Online Survey.

Purpose: Older adults aged 60 years and above are classified as being of high-risk for infection during the COVID-19 pandemic. This study aimed to investigate the associations of psychological factors (motivational factors: risk perception, health knowledge, attitude, subjective norm, motivational self-efficacy, and intention; volitional factors: volitional self-efficacy, planning, and action control) of preventive behaviors with three preventive behaviors (hand washing, facemask wearing, and social distancing) among Chinese older adults during the COVID-19 pandemic. Methods: A cross-sectional questionnaire survey was administered via SOJUMP, a widely used online survey platform in China. A total of 928 older adults (mean = 67.24 years, age range: 60-90 years, SD = 6.43, 55.9% females) were recruited using a snowball sampling approach from Hubei Province (n = 667) and outside Hubei Province (n = 261) in China during May 18, 2020 to June 7, 2020. Multiple hierarchical regressions were conducted with four models to examine the association between demographic, past behavior, psychological factors and each preventive behavior. Principal Findings: All three preventive behaviors in older adults increased dramatically during the pandemic of COVID-19. Gender, living status, educational level, past behavior, health knowledge, intention and planning significantly predicted hand washing behavior, R 2 = 0.395, F(10, 927) = 54.372, p < 0.001. Gender, education level, important others (e.g., family members or friends) infection, past behavior, health knowledge, planning and action control significantly predicted mask wearing behavior, R 2 = 0.202, F(10, 927) = 23.197, p < 0.001. Living place, past behavior and health knowledge significantly predicted social distancing behavior, R 2 = 0.204, F(9, 927) = 26.201, p < 0.001. Major Conclusions: Past behavior and health knowledge predicted all three preventive behaviors. Planning was an important psychological factor for both hand washing and mask wearing behaviors. All those critical demographic and psychological factors are critical for future interventions to facilitate older adults to comply with three preventive behaviors in daily life and to stay healthy during the COVID-19 pandemic.

Effect of therapeutic versus prophylactic anticoagulation therapy on clinical outcomes in COVID-19 patients: a systematic review with an updated meta-analysis (preprint)

Background: Previous studies demonstrate a reduced risk of thrombosis and mortality with anticoagulant treatment in patients with COVID-19 than those without anticoagulation treatment. However, an open question regarding the efficacy and safety of therapeutic anticoagulation (T-AC) versus a lower dose, prophylaxis anticoagulation (P-AC) in COVID-19 patients is still controversial. Methods: We systematically reviewed currently available randomized clinical trials (RCTs) and observational studies (OBs) from January 8, 2019, to January 8, 2022, and compared prophylactic and therapeutic anticoagulant treatment in COVID-19 patients. The primary outcomes were risk of mortality, major bleeding, and the secondary outcomes included venous and arterial thromboembolism. Subgroup analysis was also performed between critically ill and non-critically ill patients with COVID-19 and between patients with higher and lower levels of D-dimer. Sensitive analysis was performed to decrease the bias and the impact of population heterogeneity.Results: We identified 11 RCTs and 17 OBs fulfilling our inclusion criteria. In the RCTs analyses, there was no statistically significant difference in the relative risk of mortality between COVID-19 patients with T-AC treatment and those treated with P-AC (RR 0.95, 95% CI, 0.78–1.16, P = 0.61). Similar results were also found in the OBs analyses (RR 1.21, 95% CI, 0.98-1.49, P = 0.08). The pooling meta-analysis using a random-effects model combined with effect sizes showed that in the RCTs and OBs analyses, patients with COVID-19 who received T-AC treatment had a significantly higher relative risk of the major bleeding event than those with P-AC treatment in COVID-19 patients (RCTs: RR 1.76, 95% CI, 1.19-2.62, P = 0.005; OBs: RR 2.39, 95% CI, 1.56-3.68, P < 0.0001). Compared with P-AC treatment in COVID-19 patients, patients with T-AC treatment significantly reduced the incidence of venous thromboembolism (RR 0.51, 95%, 0.39-0.67, P＜0.00001), but it is not associated with arterial thrombosis events (RR 0.97, 95%, 0.66-1.42, P = 0.88). The subgroup analysis of OBs shows that the mortality risk significantly reduces in critically ill COVID-19 patients treated with T-AC compared with those with P-AC treatment (RR 0.58, 95% CI, 0.39-0.86, P = 0.007), while the mortality risk significantly increases in non-critically ill COVID-19 patients treated with T-AC (RR 1.56, 95% CI, 1.34-1.80, P < 0.00001). In addition, T-AC treatment does not reduce the risk of mortality in COVID-19 patients with high d-dimer levels in RCTs. Finally, the overall sensitivity analysis after excluding two RCTs studies remains consistent with the previous results.Conclusions: A comprehensive meta-analysis of OBs demonstrated that T-AC treatment in critically ill patients with COVID-19 significantly increased survival compared with those treated with P-AC, which was not found in the RCTs analyses. Meanwhile, P-AC treatment showed survival superiority in non-critically ill patients with COVID-19. In both RCTs and OBs, T-AC treatment in COVID-19 patients significantly reduced the incidence of venous thromboembolism but showed a higher risk of bleeding than those with P-AC treatment. Protocol registration: PROSPERO (CRD42021293294). Registered 24 November 2021.

Human Milk Antibodies after BNT162b2 Vaccination Exhibit Reduced Binding against SARS-CoV-2 Variants of Concern.

SARS-CoV-2-specific antibody responses are engendered in human milk after BNT162b2 vaccination. However, the emergence of variants of concern (VOCs) raises concerns about the specificity of and potential cross-protection mediated by milk antibody responses, which are crucial for passive immunity transferred from breastfeeding mothers to their infants. In this study, we collected milk samples at three different time points pre- and post-vaccination, and measured milk IgA antibody binding to the receptor binding domain (RBD) of the original Wuhan-Hu-1 strain, and the four VOCs, namely Alpha, Beta, Gamma and Delta. We report a significant level of anti-RBD IgA in milk collected at 4-6 weeks after the second dose of vaccination compared to pre-vaccination. We observed around a 30% reduction in binding to most VOCs, including the major circulating Delta variant, compared to the original Wuhan-Hu-1 strain. As COVID-19 vaccines may take some time to be approved for infants, these individuals remain at risk for severe disease and rely mainly on transferred passive immunity. Our findings support the current recommendations for vaccinating lactating women with the aim of transferring mucosal immunity to breastfeeding infants.