Probiotics improve symptoms of patients with COVID-19 through gut-lung axis: a systematic review and meta-analysis.

Background: Multi system symptoms such as gastrointestinal tract and respiratory tract exist in coronavirus disease 2019 (COVID-19) patients. There is a lack of reliable evidence to prove that probiotics are effective in improving these symptoms. In this study, we aimed to evaluate the efficacy of probiotics in meta-analysis. Methods: We systematically searched PubMed, Embase, Web of Science, and Cochrane Library up to February 15, 2023. Randomized controlled trials or high quality retrospective studies comparing the efficacy of probiotics as supplementation with non-probiotics in improving symptoms for patients with COVID-19 were included. This meta-analysis assessed endpoints using Review Manager 5.3. Result: Ten citations comprising 1198 patients with COVID-19 were included. The results showed that probiotics could increase the number of people with overall symptom improvement (RR = 1.62, 95% CI [1.10, 2.38], P = 0.01) and shorten the duration (days) of overall symptoms (MD = -1.26, 95% CI [-2.36, -0.16], P = 0.02). For the duration (days) of specific symptoms, probiotics could improve diarrhea (MD = -2.12, 95% CI [-2.41, -1.83], P < 0.00001), cough (MD = -2.21, 95% CI [-4.56, 0.13], P = 0.06) and shortness of breath (MD = -1.37, 95% CI [-2.22, -0.53], P = 0.001). Probiotics had no obvious effect on fever, headache and weakness. For inflammation, probiotics could effectively reduce C-reactive Protein (CRP) serum level (mg/L) (MD = -4.03, 95% CI [-5.12, -2.93], P < 0.00001). Regarding hospital stay (days), probiotics group was shorter than non-probiotics group (MD = -0.98, 95% CI [-1.95, -0.01], P = 0.05). Conclusion: To some extent probiotics could improve the overall symptoms, inflammatory reaction and shorten hospital stay of patients with COVID-19. Probiotics may improve gastrointestinal symptoms (such as improving intestinal flora and reducing the duration of diarrhea) and further improve respiratory symptoms through the gut-lung axis. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=398309, identifier: CRD42023398309.

Dependence analysis of social contact behaviors under the impacts of COVID-19 based on a copula approach.

The spread of the SARS-CoV-2 virus during the COVID-19 pandemic was intricately linked with contact between people, but many of the policies designed to encourage safe contact behaviors were unsuccessful. One reason was that the determinants of social contact decisions have not been thoroughly investigated using scientifically sound methodologies. To fill this gap, a unique survey was designed which sought data on social contact behaviors and their determinants. Second, a copula-based behavior model was developed to jointly represent the choices of contact modes (including direct and indirect contact) and the number of contacted persons. The survey was conducted in six countries from March to May 2021 and collected valid responses from >7000 people. A comparison of five key copula functions found that the Frank function outperformed the others. The results of a Frank-based model showed that indirect contacts were significantly and positively associated with the number of contacted persons. Then the influence of various determinants, including activity attributes (e.g., frequency and travel distance), protective measures, safety level of activity settings, and psychological factors related to activity participation and risk perception, were extensively analyzed. In particular, the various heterogeneous influences in different social contact settings were examined. The findings provide scientific evidence for policymakers to promote safe social distancing, even for the post-pandemic era.

Harringtonine: A more effective antagonist for Omicron variant.

Fusion with host cell membrane is the main mechanism of infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we propose that a new strategy to screen small-molecule antagonists blocking SARS-CoV-2 membrane fusion. Using cell membrane chromatography (CMC), we found that harringtonine (HT) simultaneously targeted SARS-CoV-2 S protein and host cell surface TMPRSS2 expressed by the host cell, and subsequently confirmed that HT can inhibit membrane fusion. HT effectively blocked SARS-CoV-2 original strain entry with the IC50 of 0.217 µM, while the IC50 in delta variant decreased to 0.101 µM, the IC50 in Omicron BA.1 variant was 0.042 µM. Due to high transmissibility and immune escape, Omicron subvariant BA.5 has become the dominant strain of the SARS-CoV-2 virus and led to escalating COVID-19 cases, however, against BA.5, HT showed a surprising effectiveness. The IC50 in Omicron BA.5 was even lower than 0.0019 µM. The above results revealed the effect of HT on Omicron is very significant. In summary, we characterize HT as a small-molecule antagonist by direct targeting on the Spike protein and TMPRSS2.

Stability of SARS-CoV-2 on inanimate surfaces: A review.

The stability of SARS-CoV-2 for varying periods on a wide range of inanimate surfaces has raised concerns about surface transmission; however, there is still no evidence to confirm this route. In the present review, three variables affecting virus stability, namely temperature, relative humidity (RH), and initial virus titer, were considered from different experimental studies. The stability of SARS-CoV-2 on the surfaces of six different contact materials, namely plastic, metal, glass, protective equipment, paper, and fabric, and the factors affecting half-life period was systematically reviewed. The results showed that the half-life of SARS-CoV-2 on different contact materials was generally 2-10 h, up to 5 d, and as short as 30 min at 22 °C, whereas the half-life of SARS-CoV-2 on non-porous surfaces was generally 5-9 h d, up to 3 d, and as short as 4 min at 22 â„ƒ. The half-life on porous surfaces was generally 1-5 h, up to 2 d, and as short as 13 min at 22 °C. Therefore, the half-life period of SARS-CoV-2 on non-porous surfaces is longer than that on porous surfaces, and thehalf-life of the virus decreases with increasing temperature, whereas RH produces a stable negative inhibitory effect only in a specific humidity range. Various disinfection precautions can be implemented in daily life depending on the stability of SARS-CoV-2 on different surfaces to interrupt virus transmission, prevent COVID-19 infections, and avoid over-disinfection. Owing to the more stringent control of conditions in laboratory studies and the lack of evidence of transmission through surfaces in the real world, it is difficult to provide strong evidence for the efficiency of transmission of the contaminant from the surface to the human body. Therefore, we suggest that future research should focus on exploring the systematic study of the entire transmission process of the virus, which will provide a theoretical basis for optimizing global outbreak prevention and control measures.

Efficacy and Safety of Direct Oral Anticoagulants Compared With Heparin for Preventing Thromboembolism in Hospitalized Patients With COVID-19: A Systematic Review and Meta-Analysis.

A high rate of thromboembolism and a high risk of death have been reported regarding hospitalized patients with coronavirus disease 2019 (COVID-19). Recently, we noticed that clinicians in some comparative studies used direct oral anticoagulants (DOACs) to prevent thromboembolism in patients with COVID-19. However, it is uncertain whether DOACs are better than recommended heparin for hospitalized patients with COVID-19. Therefore, a direct comparison of the prophylactic effects and safety between DOACs and heparin is needed. We systematically searched PubMed, Embase, Web of Science, and the Cochrane Library from 2019 to December 1, 2022. Randomized controlled trials or retrospective studies comparing the efficacy or safety of DOACs with that of heparin in preventing thromboembolism for hospitalized patients with COVID-19 were included. We assessed endpoints and publication bias using Stata 14.0. Five studies comprising 1360 hospitalized COVID-19 patients with mild to moderate cases were identified in the databases. Comparing the embolism incidence, we found that DOACs had a better effect than heparin, mainly low-molecular-weight heparin (LMWH), in preventing thromboembolism (risk ratio [RR] = 0.63, 95% confidence interval [CI] [0.43-0.91], P = 0.014). Considering safety, DOACs resulted in less bleeding than heparin during hospitalization (RR = 0.52, 95% CI [0.11-2.44], P = 0.411). Similar mortality was discovered in the 2 groups (RR = 0.94, 95% CI [0.59-1.51], P = 0.797). In noncritically hospitalized patients with COVID-19, DOACs are superior to heparin, even LMWH, in preventing thromboembolism. Compared with heparin, DOACs have a lower trend of bleeding and yield a similar mortality rate. Therefore, DOACs may be a better alternative for patients with mild to moderate COVID-19.

Exploration on wastewater-based epidemiology of SARS-CoV-2: Mimic relative quantification with endogenous biomarkers as internal reference.

Wastewater-based epidemiology has become a powerful surveillance tool for monitoring the pandemic of COVID-19. Although it is promising to quantitatively correlate the SARS-CoV-2 RNA concentration in wastewater with the incidence of community infection, there is still no consensus on whether the viral nucleic acid concentration in sewage should be normalized against the abundance of endogenous biomarkers and which biomarker should be used as a reference for the normalization. Here, several candidate endogenous reference biomarkers for normalization of SARS-CoV-2 signal in municipal sewage were evaluated. The human fecal indicator virus (crAssphage) is a promising candidate of endogenous reference biomarker for data normalization of both DNA and RNA viruses for its intrinsic viral nature and high and stable content in sewage. Without constructing standard curves, the relative quantification of sewage viral nucleic acid against the abundance of the reference biomarker can be used to correlate with community COVID-19 incidence, which was proved via mimic experiments by spiking pseudovirus of different concentrations in sewage samples. Dilution of pseudovirus-seeded wastewater did not affect the relative abundance of viral nucleic acid, demonstrating that relative quantification can overcome the sewage dilution effects caused by the greywater input, precipitation and/or groundwater infiltration. The process of concentration, recovery and detection of the endogenous biomarker was consistent with that of SARS-CoV-2 RNA. Thus, it is necessary to co-quantify the endogenous biomarker because it can be not only an internal reference for data normalization, but also a process control.

Stability of SARS-CoV-2 on Inanimate Surfaces: A Review

The stability of SARS-CoV-2 for varying periods on a wide range of inanimate surfaces has raised concerns about surface transmission;however, there is still no evidence to confirm this route. In the present review, three variables affecting virus stability, namely temperature, relative humidity (RH), and initial virus titer, were considered from different experimental studies. The stability of SARS-CoV-2 on the surfaces of six different contact materials, namely plastic, metal, glass, protective equipment, paper, and fabric, and the factors affecting half-life period was systematically reviewed. The results showed that the half-life of SARS-CoV-2 on different contact materials was generally 2–10 h, up to 5 d, and as short as 30 min at 22°C, whereas the half-life of SARS-CoV-2 on non-porous surfaces was generally 5–9 h d, up to 3 d, and as short as 4 min at 22℃. The half-life on porous surfaces was generally 1–5 h, up to 2 d, and as short as 13 min at 22°C. Therefore, the half-life period of SARS-CoV-2 on non-porous surfaces is longer than that on porous surfaces, and thehalf-life of the virus decreases with increasing temperature, whereas RH produces a stable negative inhibitory effect only in a specific humidity range. Various disinfection precautions can be implemented in daily life depending on the stability of SARS-CoV-2 on different surfaces to interrupt virus transmission, prevent COVID-19 infections, and avoid over-disinfection. Owing to the more stringent control of conditions in laboratory studies and the lack of evidence of transmission through surfaces in the real world, it is difficult to provide strong evidence for the efficiency of transmission of the contaminant from the surface to the human body. Therefore, we suggest that future research should focus on exploring the systematic study of the entire transmission process of the virus, which will provide a theoretical basis for optimizing global outbreak prevention and control measures.

Assessing the transmissibility of epidemics involving epidemic zoning.

BACKGROUND: Epidemic zoning is an important option in a series of measures for the prevention and control of infectious diseases. We aim to accurately assess the disease transmission process by considering the epidemic zoning, and we take two epidemics with distinct outbreak sizes as an example, i.e., the Xi'an epidemic in late 2021 and the Shanghai epidemic in early 2022. METHODS: For the two epidemics, the total cases were clearly distinguished by their reporting zone and the Bernoulli counting process was used to describe whether one infected case in society would be reported in control zones or not. Assuming the imperfect or perfect isolation policy in control zones, the transmission processes are respectively simulated by the adjusted renewal equation with case importation, which can be derived on the basis of the Bellman-Harris branching theory. The likelihood function containing unknown parameters is then constructed by assuming the daily number of new cases reported in control zones follows a Poisson distribution. All the unknown parameters were obtained by the maximum likelihood estimation. RESULTS: For both epidemics, the internal infections characterized by subcritical transmission within the control zones were verified, and the median control reproduction numbers were estimated as 0.403 (95% confidence interval (CI): 0.352, 0.459) in Xi'an epidemic and 0.727 (95% CI: 0.724, 0.730) in Shanghai epidemic, respectively. In addition, although the detection rate of social cases quickly increased to 100% during the decline period of daily new cases until the end of the epidemic, the detection rate in Xi'an was significantly higher than that in Shanghai in the previous period. CONCLUSIONS: The comparative analysis of the two epidemics with different consequences highlights the role of the higher detection rate of social cases since the beginning of the epidemic and the reduced transmission risk in control zones throughout the outbreak. Strengthening the detection of social infection and strictly implementing the isolation policy are of great significance to avoid a larger-scale epidemic.

The dynamic changes of psychosomatic symptoms in three waves of COVID-19 outbreak and fatigue caused by enduring pandemic in China.

BACKGROUND: Two years have passed since the 2019 novel coronavirus disease (COVID-19) was first reported. The persistent pandemic might lead to severe psychosomatic problems and fatigue. In addition, the recent rapid rising COVID-19 cases in China have become a trending issue. Therefore, this study aimed to investigate the dynamic changes in psychosomatic problems at the initial and current stages of the pandemic. METHODS: Three waves of cross-sectional online survey were conducted during the initial COVID outbreak in China. The psychosomatic symptom scale (PSSS), perceived stress scale (PSS), and pandemic fatigue scale (PFS) were used to assess the psychosomatic problems, stress, and fatigue. RESULTS: 4317, 1096, and 2172 participants completed the first, second, and third surveys. The prevalence of psychosomatic disorder was 22 %, 28 %, and 39 %, respectively. The network structure of PSSS symptoms has not significantly changed as the pandemic progresses. However, the global strength of the PSSS networks, indicating the overall connectivity, in the third wave was significantly higher than in the first wave (s = 0.54, P = 0.007). The most central symptoms in the first and third wave networks were depressed mood and tiredness. The PFS score was higher in the people concerned with indirect impact than those concerned with health (P < 0.001). PFS has positive relationships with PSSS and PSS score (R = 0.41, P < 0.001 and R = 0.35, P < 0.001, respectively). CONCLUSIONS: The persistence of the pandemic caused critical psychosomatic issues, stress, and indirect burden over time, leading to inevitable fatigue. People endured needing immediate attention to prevent or reduce psychosomatic disorders.

Investigating sleep quality and sleep hygiene awareness among Chinese adults: an association and network analysis study.

PURPOSE: The relationships between sleep quality and sleep hygiene awareness in the Chinese population were unclear. We aimed to investigate the associations and related factors between sleep quality and sleep hygiene awareness in adults and to identify the most central domain for sleep quality using network analysis. METHODS: A cross-sectional survey was conducted from April 22 to May 5, 2020. Adults (18 years old or above) who had access to smartphones were invited to participate in this survey. The Pittsburg Sleep Quality Index (PSQI) and the Sleep Hygiene Awareness and Practice Scale (SHAPS) were used to evaluate the sleep quality and sleep hygiene awareness of the participants. Propensity score matching (PSM) was used as sensitivity analysis to reduce the confounding effects. Multiple logistic regression was performed to evaluate the associations. The R packages "bootnet" and "qgraph" were used to estimate the connection and calculate the network centrality indices between good and poor sleepers. RESULTS: In total, 939 respondents were included in the analysis. Of them, 48.8% (95% CI: 45.6-52.0%) were identified as poor sleepers. Participants with nervous system diseases, psychiatric diseases, and psychological problems were more likely to have poor sleep quality. The notion that using sleep medication regularly was beneficial to sleep was associated with poor sleep quality. Similarly, the notion that waking up at the same time each day disrupted sleep was also associated with poor sleep quality. The findings were consistent before and after PSM. Subjective sleep quality was the most central domain for sleep quality in good and poor sleepers. CONCLUSION: Poor sleep quality was positively associated with certain sleep hygiene notions in Chinese adults. Effective measures such as self-relief, sleep hygiene education, and cognitive behavioral treatment may have been needed to improve sleep quality, especially during the COVID-19 outbreak.

How does interactive virtual reality enhance learning outcomes via emotional experiences? A structural equation modeling approach.

Introduction: Interest in interactive virtual reality (IVR) is increasing due to its potential for embodied learning and group-led teaching. However, few studies have investigated the internal mechanism by which IVR technology features and learning experiences affect learning outcomes in terms of psychological and emotional value. Based on media technology models and the control value theory of achievement emotions (CVTAE), this study uses structural equation modeling (SEM) to investigate the correlations among the internal elements of IVR technology features, learning experiences, and learning outcomes. It also emphasizes the role played by emotional experience in this context. Methods: The sample referenced by this study consisted of 480 college students (193 males) who were simultaneously engaged in guided inquiry and learning in an IVR-based COVID-19 pandemic science museum in groups of 10. Results: The findings suggest that presence and perceived enjoyment have a key mediating effect on the relationship between virtual reality (VR) features and perceived learning outcomes in an IVR-based learning simulation. In addition, the results indicate that presence is more strongly correlated with perceived learning effects, while enjoyment is more strongly correlated with learning satisfaction. Discussion: These findings provide intellectual support and theoretical backing for VR-based instructional design and environmental development. Moreover, this study has practical value with regard to the future large-scale application of IVR to experiential teaching, group-led teaching, and the promotion of the digital transformation and intelligence upgrading in education.

Auxiliary signal-guided knowledge encoder-decoder for medical report generation.

Medical reports have significant clinical value to radiologists and specialists, especially during a pandemic like COVID. However, beyond the common difficulties faced in the natural image captioning, medical report generation specifically requires the model to describe a medical image with a fine-grained and semantic-coherence paragraph that should satisfy both medical commonsense and logic. Previous works generally extract the global image features and attempt to generate a paragraph that is similar to referenced reports; however, this approach has two limitations. Firstly, the regions of primary interest to radiologists are usually located in a small area of the global image, meaning that the remainder parts of the image could be considered as irrelevant noise in the training procedure. Secondly, there are many similar sentences used in each medical report to describe the normal regions of the image, which causes serious data bias. This deviation is likely to teach models to generate these inessential sentences on a regular basis. To address these problems, we propose an Auxiliary Signal-Guided Knowledge Encoder-Decoder (ASGK) to mimic radiologists' working patterns. Specifically, the auxiliary patches are explored to expand the widely used visual patch features before fed to the Transformer encoder, while the external linguistic signals help the decoder better master prior knowledge during the pre-training process. Our approach performs well on common benchmarks, including CX-CHR, IU X-Ray, and COVID-19 CT Report dataset (COV-CTR), demonstrating combining auxiliary signals with transformer architecture can bring a significant improvement in terms of medical report generation. The experimental results confirm that auxiliary signals driven Transformer-based models are with solid capabilities to outperform previous approaches on both medical terminology classification and paragraph generation metrics.

Early warning signals for Omicron outbreaks in China: a retrospective study.

The Omicron variant has become the dominant COVID-19 variant worldwide due to its rapid and cryptic spread; therefore, successful early warning is of great importance to be able to control epidemics in their early phase, before developing into large outbreaks. COVID-19-related Baidu search index, which reflects human behavior to a certain degree, was used to retrospectively detect the warning signs for Omicron variant outbreaks in China in 2022. The characteristics and effects of warning signs were analyzed in detail. We detected the presence of early warning signs (both high and low thresholds) and found that these occurred 4-7 days earlier than traditional epidemiological surveillance and >20 days earlier than the implementation of the local "lockdown" policy. Compared with the "high threshold" warning, the early warning effect of the "low threshold" is also vital because it indicates a complacency about epidemic prevention and control. However, there is obvious heterogeneity in the optimal threshold for detecting early warning signs and their distribution in different cities. Multi-source and multi-point early warning systems should be established via combining internet-based big data in the future to conduct effective and early real-time warning. This would create precious time for the early control of COVID-19 outbreaks. This article is protected by copyright. All rights reserved.

Chiral-Selective Antigen-Presentation by Supramolecular Chiral Polymer Micelles.

Chirality is ubiquitous in biological systems, which is closely related to biological functions, life process, and even pathogenesis of diseases. However, the interface between the chirality of synthetic materials and organisms, particularly the immune system, remains poorly understood. Here, supramolecular chiral polymer micelles (SCPMs) are prepared by complexing antigenic proteins with chiral amino acid modified polyethyleneimine. The introduction of chirality not only reduces the toxicity of cationic polymer, but also benefits cell uptake and antigen presentation. Especially, D-chirality presents the lowest cytotoxicity, while promotes the highest expression level of costimulatory molecules on dendritic cells compared to L-chirality and achirality. The superiority of D-chirality to stimulate dendritic cell maturation is supported by immunization with D-SCPMs, which achieves significant antigen-specific proliferation of T cells in the spleen, lymph nodes and tumor of mice. Chirality-mediated antigen processing and presentation is demonstrated by D-SCPMs self-assembled from chiral alkaline histidine or neutral phenylalanine modified polyethyleneimine and tumor associated ovalbumin or severe acute respiratory syndrome coronavirus 2 spike 1 antigenic protein. Immunoactivation enabled by D-chirality opens a window to prepare potent nanotherapeutics for disease prevention and treatment. This article is protected by copyright. All rights reserved.

Optimizing the nucleic acid screening strategy to mitigate regional outbreaks of SARS-CoV-2 Omicron variant in China: a modeling study.

BACKGROUND: The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads rapidly and insidiously. Coronavirus disease 2019 (COVID-19) screening is an important means of blocking community transmission in China, but the costs associated with testing are high. Quarantine capacity and medical resources are also threatened. Therefore, we aimed to evaluate different screening strategies to balance outbreak control and consumption of resources. METHODS: A community network of 2000 people, considering the heterogeneities of household size and age structure, was generated to reflect real contact networks, and a stochastic individual-based dynamic model was used to simulate SARS-CoV-2 transmission and assess different whole-area nucleic acid screening strategies. We designed a total of 87 screening strategies with different sampling methods, frequencies of screening, and timings of screening. The performance of these strategies was comprehensively evaluated by comparing the cumulative infection rates, the number of tests, and the quarantine capacity and consumption of medical resource, which were expressed as medians (95% uncertainty intervals, 95% UIs). RESULTS: To implement COVID-19 nucleic acid testing for all people (Full Screening), if the screening frequency was four times/week, the cumulative infection rate could be reduced to 13% (95% UI: 1%, 51%), the miss rate decreased to 2% (95% UI: 0%, 22%), and the quarantine and medical resource consumption was lower than higher-frequency Full Screening or sampling screening. When the frequency of Full Screening increased from five to seven times/week (which resulted in a 2581 increase in the number of tests per positive case), the cumulative infection rate was only reduced by 2%. Screening all people weekly by splitting them equally into seven batches could reduce infection rates by 73% compared to once per week, which was similar to Full Screening four times/week. Full Screening had the highest number of tests per positive case, while the miss rate, number of tests per positive case, and hotel quarantine resource consumption in Household-based Sampling Screening scenarios were lower than Random Sampling Screening. The cumulative infection rate of Household-based Sampling Screening or Random Sampling Screening seven times/week was similar to that of Full Screening four times/week. CONCLUSIONS: If hotel quarantine, hospital and shelter hospital capacity are seriously insufficient, to stop the spread of the virus as early as possible, high-frequency Full Screening would be necessary, but intermediate testing frequency may be more cost-effective in non-extreme situations. Screening in batches is recommended if the testing capacity is low. Household-based Sampling Screening is potentially a promising strategy to implement.

Biological effect of black phosphorus nanosheets on the interaction between SARS-CoV-2 S protein and ACE2.

The binding of the spike glycoprotein (S protein) in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to angiotensin-converting enzyme 2 (ACE2) is the main pathway that leads to serious coronavirus disease 2019 (COVID-19) infection. In the biomedical applications of various nanomaterials, black phosphorus nanosheets (BP) have been receiving increasing attention owing to their excellent characteristics. In this study, the biological effect of BP on the interaction between the S protein and ACE2 was investigated by molecular dynamics simulations. The results indicated that the ACE2 could be quickly and stably adsorbed on the BP surface by non-specific binding and retain its structural integrity. Compared with the case without BP, the interaction of the S protein bound to ACE2 adsorbed on the BP surface was greatly weakened, including hydrogen bonds, salt bridges, and van der Waals forces. This study not only reveals that BP could effectively obstruct the binding of S protein and ACE2, which may provide a potential and reasonable drug carrier to further enhance the curative effect of inhibitors against SARS-CoV-2 infection, but also presents a novel interference mechanism for protein-protein interactions caused by nanomaterials.

Diagnostic value of determination of plasma CRP, PCT and IL-6 levels in patients with COVID-19

The article's objective was to assess the clinical diagnostic utility of plasma levels of CRP, PCT, and IL-6 in individuals with COVID-19 both alone and in combination. Results showed that according to the ROC curve, PCT and CRP were highly valuable in the diagnosis of COVID-19, and CRP was most valuable in the evaluation of patients with severe and critical COVID-19. The combined detection of the three indexes might increase the evaluation's effectiveness. When evaluating COVID-19 patients who were in severe condition, IL-6 demonstrated a strong predictive value. Therefore, combining the three indicators may increase the diagnostic efficiency and provide crucial reference values for the clinical diagnosis and treatment of COVID-19. CRP, PCT, and IL-6 levels may be potential biomarkers for the diagnosis of COVID-19 and can be used to determine the severity of COVID-19.

Social contact patterns and changes at leisure/tourism activity settings during COVID-19 period: An international comparison

Social contacts are an important indicator to track the spread of pandemics and evaluate the effectiveness of policy interventions in specific settings. Using a retrospective survey, this chapter compared the reported contact patterns during the COVID-19 outbreak to contact patterns during the influenza period in leisure/tourism settings of four developed countries. Changes in social contact patterns across demographic and other factors at different locations and regions are identified, which are helpful for classifying the heterogeneity of contact patterns and potential post-lockdown transmission patterns. This analysis can assist policymakers to implement more evidence-based interventions to guide the economic recovery of the tourism sector.

Tourism policy responses to COVID-19 and first-stage tourism recovery in China

In order to find a coordinated approach to support tourism recovery following the impacts of COVID-19, this research examines the experiences of mainland China, the first country whose domestic tourism recovered in the first stage (the first year after the pandemic outbreak). Through the content analysis of tourism policy documents at national, provincial, and city levels, we generated the features of the policy responses from the supply and demand sides, and the policy trends before and after the first peak of the recovery. Next, we summarized the three steps which make up the first stage, and describe the effective policy focus for each step. This process-oriented policy analysis can guide other countries in how to cope with tourism recovery during the first stage.