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1.
medrxiv; 2023.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2023.05.12.23289890

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic and the measures taken by authorities to control its spread had altered human behavior and mobility patterns in an unprecedented way. However, it remains unclear whether the population response to a COVID-19 outbreak varies within a city or among demographic groups. Here we utilized passively recorded cellular signaling data at a spatial resolution of 1km x 1km for over 5 million users and epidemiological surveillance data collected during the SARS-CoV-2 Omicron BA.2 outbreak from February to June 2022 in Shanghai, China, to investigate the heterogeneous response of different segments of the population at the within-city level and examine its relationship with the actual risk of infection. Changes in behavior were spatially heterogenous within the city and population groups, and associated with both the infection incidence and adopted interventions. We also found that males and individuals aged 30-59 years old traveled more frequently, traveled longer distances, and their communities were more connected; the same groups were also associated with the highest SARS-CoV-2 incidence. Our results highlight the heterogeneous behavioral change of the Shanghai population to the SARS-CoV-2 Omicron BA.2 outbreak and the its effect on the heterogenous spread of COVID-19, both spatially and demographically. These findings could be instrumental for the design of targeted interventions for the control and mitigation of future outbreaks of COVID-19 and, more broadly, of respiratory pathogens.


Subject(s)
COVID-19
2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(1): 92-105, 2023 Jan 28.
Article in English, Chinese | MEDLINE | ID: covidwho-2288573

ABSTRACT

OBJECTIVES: Shelter hospital was an alternative way to provide large-scale medical isolation and treatment for people with mild coronavirus disease 2019 (COVID-19). Due to various reasons, patients admitted to the large shelter hospital was reported high level of psychological distress, so did the healthcare workers. This study aims to introduce a comprehensive and multifaceted psychosocial crisis intervention model. METHODS: The psychosocial crisis intervention model was provided to 200 patients and 240 healthcare workers in Wuhan Wuchang shelter hospital. Patient volunteers and organized peer support, client-centered culturally sensitive supportive care, timely delivery of scientific information about COVID-19 and its complications, mental health knowledge acquisition of non-psychiatric healthcare workers, group activities, counseling and education, virtualization of psychological intervention, consultation and liaison were exhibited respectively in the model. Pre-service survey was done in 38 patients and 49 healthcare workers using the Generalized Anxiety Disorder 7-item (GAD-7) scale, the Patient Health Questionnaire 2-item (PHQ-2) scale, and the Primary Care PTSD screen for the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (PC-PTSD-5). Forty-eight healthcare workers gave feedback after the intervention. RESULTS: The psychosocial crisis intervention model was successfully implemented by 10 mental health professionals and was well-accepted by both patients and healthcare workers in the shelter hospital. In pre-service survey, 15.8% of 38 patients were with anxiety, 55.3% were with stress, and 15.8% were with depression; 16.3% of 49 healthcare workers were with anxiety, 26.5% were with stress, and 22.4% were with depression. In post-service survey, 62.5% of 48 healthcare workers thought it was very practical, 37.5% thought more practical; 37.5% of them thought it was very helpful to relief anxiety and insomnia, and 27.1% thought much helpful; 37.5% of them thought it was very helpful to recognize patients with anxiety and insomnia, and 29.2% thought much helpful; 35.4% of them thought it was very helpful to deal with patients' anxiety and insomnia, and 37.5% thought much helpful. CONCLUSIONS: Psychological crisis intervention is feasible, acceptable, and associated with positive outcomes. Future tastings of this model in larger population and different settings are warranted.


Subject(s)
COVID-19 , Sleep Initiation and Maintenance Disorders , Humans , Crisis Intervention , Psychosocial Intervention , SARS-CoV-2 , Mental Health , Depression/epidemiology , Health Personnel/psychology , Anxiety/therapy , Anxiety/etiology
3.
biorxiv; 2023.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2023.04.09.536130

ABSTRACT

The blood proteome holds great promise for precision medicine but poses daunting challenges due to the low abundance of the majority of plasma proteins and the vast dynamic range across the proteome. We report the development and validation of a novel proteomic analysis technology - NUcleic acid Linked Immuno-Sandwich Assay (NULISA) - that incorporates a dual capture and release mechanism to suppress the assay background to the minimum, thus drastically improving the signal-to-noise ratio. NULISA improves the sensitivity of the proximity ligation assay by over 10,000-fold to the attomolar level, which is enabled by antibody-conjugated DNA sequences that mediate the purification of immunocomplexes and contain target- and sample-specific barcodes for next-generation sequencing-based, highly multiplexed analysis. To demonstrate its performance and utility, we developed a 200-plex NULISA targeting 124 cytokines and chemokines and 80 other immune response-related proteins that demonstrated superior sensitivity for detecting low-abundance proteins and high concordance with other immunoassays. The ultra-high sensitivity enabled the detection of previously difficult-to-detect but biologically important, low-abundance biomarkers in patients with autoimmune diseases and COVID-19. Fully automated NULISA uniquely addresses longstanding challenges in the proteomic analysis of liquid biopsy samples and makes broad and in-depth proteomic analysis accessible to the general research community and future diagnostic applications.


Subject(s)
COVID-19 , Autoimmune Diseases
4.
Journal of Contingencies & Crisis Management ; : 1.0, 2023.
Article in English | Academic Search Complete | ID: covidwho-2228849

ABSTRACT

Public efficacy beliefs against COVID‐19 might affect a person's coping strategy toward infection control. This study presented a synthetic conceptual model based on the Integrative Model of Behavioural Prediction (IMBP). We examined inductively the relationships among media exposure, efficacy beliefs, attribution of responsibilities and recommended protective behavioural intention using a survey of 435 participants who experienced the epidemic in China. Results suggest that traditional media exposure could stably and consistently enhance people's self‐efficacy, collective efficacy as well as proxy efficacy, whereas social media exposure only increases the degree of self‐efficacy. Furthermore, we detect that protective behavioural intention is directly affected by self‐efficacy and indirectly affected by collective efficacy and proxy efficacy via the mediation of self‐efficacy. At the same time, the influence of self‐efficacy on attribution of responsibilities and protective behaviours can be moderated by collective efficacy and proxy efficacy, respectively. [ FROM AUTHOR]

5.
Int Immunopharmacol ; 115: 109728, 2023 Feb.
Article in English | MEDLINE | ID: covidwho-2179733

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and monkeypox virus (MPXV) severely threaten human health; however, currently, no vaccine can prevent a co-infection with both viruses. METHODS: Five antigens were selected to predict dominant T and B cell epitopes screened for immunogenicity, antigenicity, toxicity, and sensitization. After screening, all antigens joined in the construction of a novel multiepitope vaccine. The physicochemical and immunological characteristics, and secondary and tertiary structures of the vaccine were predicted and analyzed using bio- and immunoinformatics. Finally, codon optimization and cloning in-silico were performed. RESULTS: A new multiepitope vaccine, named S7M8, was constructed based on four helper T lymphocyte (HTL) epitopes, six cytotoxic T lymphocyte (CTL) epitopes, five B cell epitopes, as well as Toll-like receptor (TLR) agonists. The antigenicity and immunogenicity scores of the S7M8 vaccine were 0.907374 and 0.6552, respectively. The S7M8 vaccine was comprised of 26.96% α-helices, the optimized Z-value of the tertiary structure was -5.92, and the favored area after majorization in the Ramachandran plot was 84.54%. Molecular docking showed that the S7M8 vaccine could tightly bind to TLR2 (-1100.6 kcal/mol) and TLR4 (-950.3 kcal/mol). In addition, the immune stimulation prediction indicated that the S7M8 vaccine could activate T and B lymphocytes to produce high levels of Th1 cytokines and antibodies. CONCLUSION: S7M8 is a promising biomarker with good antigenicity, immunogenicity, non-toxicity, and non-sensitization. The S7M8 vaccine can trigger significantly high levels of Th1 cytokines and antibodies and may be a potentially powerful tool in preventing SARS-CoV-2 and MPXV.


Subject(s)
COVID-19 , Coinfection , Humans , SARS-CoV-2 , COVID-19/prevention & control , Epitopes, B-Lymphocyte , Monkeypox virus , Molecular Docking Simulation , Vaccinology , Epitopes, T-Lymphocyte , Vaccines, Subunit , Cytokines , Computational Biology
6.
J Pers Med ; 13(1)2023 Jan 05.
Article in English | MEDLINE | ID: covidwho-2166674

ABSTRACT

(1) Background: Many co-infections of Mycobacterium tuberculosis (MTB) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have emerged since the occurrence of the SARS-CoV-2 pandemic. This study aims to design an effective preventive multi-epitope vaccine against the co-infection of MTB and SARS-CoV-2. (2) Methods: The three selected proteins (spike protein, diacylglycerol acyltransferase, and low molecular weight T-cell antigen TB8.4) were predicted using bioinformatics, and 16 epitopes with the highest ranks (10 helper T lymphocyte epitopes, 2 CD8+ T lymphocytes epitopes, and 4 B-cell epitopes) were selected and assembled into the candidate vaccine referred to as S7D5L4. The toxicity, sensitization, stability, solubility, antigenicity, and immunogenicity of the S7D5L4 vaccine were evaluated using bioinformatics tools. Subsequently, toll-like receptor 4 docking simulation and discontinuous B-cell epitope prediction were performed. Immune simulation and codon optimization were carried out using immunoinformatics and molecular biology tools. (3) Results: The S7D5L4 vaccine showed good physical properties, such as solubility, stability, non-sensitization, and non-toxicity. This vaccine had excellent antigenicity and immunogenicity and could successfully simulate immune responses in silico. Furthermore, the normal mode analysis of the S7D5L4 vaccine and toll-like receptor 4 docking simulation demonstrated that the vaccine had docking potential and a stable reaction. (4) Conclusions: The S7D5L4 vaccine designed to fight against the co-infection of MTB and SARS-CoV-2 may be safe and effective. The protective efficacy of this promising vaccine should be further verified using in vitro and in vivo experiments.

7.
J Affect Disord ; 324: 600-606, 2023 03 01.
Article in English | MEDLINE | ID: covidwho-2165459

ABSTRACT

BACKGROUND: Studying the role of psychological resilience in self-perceived stress and mental disorders among family members of medical workers can help us understand its importance in mental health care and guide us to develop psychological intervention strategies for family members of medical workers. METHODS: A total of 671 family members of medical workers were enrolled. Self-perceived stress, resilience, depression symptoms, anxiety symptoms, and post-traumatic stress disorder (PTSD) symptoms were measured in our research. RESULTS: The prevalence of anxiety, depression, and PTSD symptoms among relatives of medical workers were 49.0 %, 12.2 %, and 20.3 % respectively during the COVID-19 epidemic. According to the Multivariate regression model, compared with family members of doctor, family members of nurse and medical technologists were more likely to report anxiety symptoms. Female members of medical staff were more likely to have PTSD symptoms than male counterparts; and family members of medical technologist appeared to less likely have PTSD symptoms than family members of either doctor or nurse. The mediation analysis confirmed that mental resilience mediated the relationship between self-perceived stress and anxiety symptoms. LIMITATIONS: Single cross-sectional study design without the follow-up comparative analysis, only self-reported measurements were adopted, and inadequate pre-set demographic variables. CONCLUSIONS: To the best of our knowledge, our study firstly demonstrated the risk of psychological distress present in the family members of medical providers during the COVID-19 epidemic. Meanwhile, our findings highlighted the importance of mental resilience in family members of frontline medical workers as it mediated the relationship between self-perceived stress and anxiety symptoms.


Subject(s)
COVID-19 , Stress Disorders, Post-Traumatic , Humans , Male , Female , SARS-CoV-2 , Cross-Sectional Studies , Depression/epidemiology , Depression/psychology , Mental Health , Health Personnel/psychology , Anxiety/epidemiology , Anxiety/psychology , Stress Disorders, Post-Traumatic/epidemiology
8.
Clinical Nephrology ; 96(4):207-215, 2021.
Article in English | GIM | ID: covidwho-2056047

ABSTRACT

Background: Continuous renal replacement therapy (CRRT) has become an important multiple organ support therapy and it is widely used in the intensive care unit (ICU). The aim of this study was to clarify the association between CRT and 28-day mortality in critically ill coronavirus disease 2019 (COVID-19) patients receiving mechanical ventilation. Materials and methods: 112 respiratory decompensated critically ill adult patients with COVID-19 admitted to a COVID-19-designated ICU were included in this retrospective cohort study. Data on demographic information, comorbidities, laboratory findings upon ICU admission, and clinical outcomes were collected. The Kaplan-Meier method and Cox proportional hazard model were applied to determine the potential risk factors associated with 28-day mortality.

9.
Security and Communication Networks ; 2022, 2022.
Article in English | ProQuest Central | ID: covidwho-2053442

ABSTRACT

Since the outbreak of COVID-19, the cross-border e-commerce platform has been rising rapidly because of its unique advantages. However, with the widespread application of information technologies such as mobile Internet and big data, fundamental changes have taken place in consumer preferences, consumption patterns, and marketing channels in cross-border e-commerce platforms. They also change the logic of value co-creation (VCC). The platform can achieve survive, expansion, and sustainable development by realising the value co-creation of the whole platform ecosystem. Based on the perspective of the platform ecosystem, this paper uses the grounded theory analysis method and NVivo 11.0 software carries out three-level coding on the obtained original data, and finally summarises and extracts four core categories of value co-creation mechanism: connection and interaction of value co-creators, demand mining, resource integration, and system support. The first two categories reflect stakeholders’ internal connection and interaction mechanism, and the last two categories reflect the external support mechanism in value co-creation.

11.
biorxiv; 2022.
Preprint in English | bioRxiv | ID: ppzbmed-10.1101.2022.05.13.491759

ABSTRACT

Among the current five Variants of Concern, infections caused by the SARS-CoV-2 B.1.617.2 (Delta) variant are often associated with the greatest severity. Despite recent advances on the molecular basis of elevated pathogenicity using recombinant proteins, architecture of intact Delta virions remains veiled. Moreover, the detailed mechanism of S-mediated membrane fusion remains elusive. Here we report the molecular assembly and fusion snapshots of the authentic Delta variant. Envelope invagination and fusion events were frequently observed. Native structures of pre- and postfusion S were determined up to 4.1-A resolution. Site-specific glycan analysis revealed increased oligomannose-type glycosylation of native Delta S over that of the Wuhan-Hu-1 S. Based on these findings, we proposed a model for S-mediated membrane fusion and a model for the invagination formation.

12.
researchsquare; 2022.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-1478539.v1

ABSTRACT

After the adoption of a dynamic zero-COVID strategy in China for nearly two years, whether and for how long this policy can remain in place is unclear. The debate has thus shifted towards the identification of mitigation strategies capable to prevent the disruption of the healthcare system, should a nationwide epidemic caused by the SARS-CoV-2 Omicron variant start to unfold. To this aim, we developed a mathematical model of SARS-CoV-2 transmission tailored to the unique immunization and epidemiological situation of China. We find that the level of immunity induced by the current vaccination campaign would be insufficient to prevent overwhelming the healthcare system and major losses of human lives. Instead, a synergetic strategy would be needed and based on 1) a heterologous booster vaccination campaign, 2) treating 50% of symptomatic cases with an antiviral with an 80% efficacy in preventing severe outcomes, and 3) the adoption of non-pharmaceutical interventions (NPIs) capable of reducing Rt to ≤2. Protecting vulnerable individuals by ensuring accessibility to vaccines and antivirals, and maintaining a certain degree of NPIs should be emphasised in a future mitigation policy, possibly supported by strengthening critical care capacity and the development of highly efficacious vaccines with long-lasting immunity.

13.
Frontiers in immunology ; 13, 2022.
Article in English | EuropePMC | ID: covidwho-1678838

ABSTRACT

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. As a result of the coronavirus disease 2019 (COVID-19) pandemic, the global TB mortality rate in 2020 is rising, making TB prevention and control more challenging. Vaccination has been considered the best approach to reduce the TB burden. Unfortunately, BCG, the only TB vaccine currently approved for use, offers some protection against childhood TB but is less effective in adults. Therefore, it is urgent to develop new TB vaccines that are more effective than BCG. Accumulating data indicated that peptides or epitopes play essential roles in bridging innate and adaptive immunity and triggering adaptive immunity. Furthermore, innovations in bioinformatics, immunoinformatics, synthetic technologies, new materials, and transgenic animal models have put wings on the research of peptide-based vaccines for TB. Hence, this review seeks to give an overview of current tools that can be used to design a peptide-based vaccine, the research status of peptide-based vaccines for TB, protein-based bacterial vaccine delivery systems, and animal models for the peptide-based vaccines. These explorations will provide approaches and strategies for developing safer and more effective peptide-based vaccines and contribute to achieving the WHO’s End TB Strategy.

14.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.10.25.21265504

ABSTRACT

Summary Background Hundreds of millions of doses of COVID-19 vaccines have been administered globally, but progress in vaccination varies considerably between countries. We aim to provide an overall picture of COVID-19 vaccination campaigns, including policy, coverage, and demand of COVID-19 vaccines. Methods We conducted a descriptive study of vaccination policy and doses administered data obtained from multiple public sources as of 23 October 2021. We used these data to develop coverage indicators and explore associations of vaccine coverage with socioeconomic and healthcare-related factors. We estimated vaccine demand as numbers of doses required to complete vaccination of target populations of countries according to their national immunization program policies. Findings Use of both mRNA and adenovirus vectored vaccines was the most commonly used COVID-19 vaccines formulary in high-income countries, while adenovirus vectored vaccines were the most widely used vaccines worldwide (176 countries). Almost all countries (98.3%, 173/176) have authorized vaccines for the general public, with 53.4% (94/176) targeting individuals over 12 years and 33.0% (58/176) targeting those [≥]18 years. Forty-one and sixty-seven countries have started additional-dose and booster-dose vaccination programs, respectively. Globally, there have been 116.5 doses administered per 100 target population, although with marked inter-region and inter-country heterogeneity. Completed vaccination series coverage ranged from 0% to more than 95.0% of country target populations, and numbers of doses administered ranged from 0 to 239.6 per 100 target population. Doses administered per 100 total population correlated with healthcare access and quality index (R2 = 0.58), socio-demographic index (R2 = 0.56), and GDP per capita (R2 = 0.65). At least 5.54 billion doses will be required to complete interim vaccination programs: 4.65 billion for primary immunization and 0.89 billion for additional/booster programs. Globally, 0.84 and 0.96 dose per individual in the target population are needed for primary immunization and additional/booster programs, respectively. Interpretation There is wide country-level disparity and inequity in COVID-19 vaccines rollout, suggesting large gaps in immunity, especially in low-income countries.


Subject(s)
COVID-19
15.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.10.14.21265032

ABSTRACT

Objectives SARS-CoV-2 infection causes most cases of severe illness and fatality in older age groups. In China, over 99% of individuals aged ⩾12 years have been fully vaccinated against COVID-19 (albeit with vaccines developed against historical lineages), while 65.0% children aged 3–11 years have been vaccinated their first doses (as of November 12, 2021). Here, we aimed to assess whether, in this vaccination landscape, the importation of Delta variant infections could shift the COVID-19 burden from adults to children. Methods We developed an age-structured susceptible-infectious-removed model of SARS-CoV-2 transmission dynamics to simulate epidemics triggered by the importation of Delta variant infections and project the age-specific incidence of SARS-CoV-2 infections, cases, hospitalisations, intensive care unit (ICU) admissions, and deaths. Results In the context of the vaccination programme targeting individuals aged ≥12 years (as it was the case until mid-October 2021), and in the absence of non-pharmaceutical interventions, the importation of Delta variant infections could have led to widespread transmission and substantial disease burden in mainland China, even with vaccination coverage as high as 97% across the eligible age groups. Extending the vaccination roll-out to include children aged 3–11 years (as it was the case since the end of October 2021) is estimated to dramatically decrease the burden of symptomatic infections and hospitalisations within this age group (54% and 81%, respectively, when considering a vaccination coverage of 99%), but would have a low impact on protecting infants (aged 0–2 years). Conclusions Our findings highlight the importance of including children among the target population and the need to strengthen vaccination efforts by increasing vaccine effectiveness.


Subject(s)
COVID-19 , Infections
16.
Front Psychiatry ; 12: 695678, 2021.
Article in English | MEDLINE | ID: covidwho-1448815

ABSTRACT

Background: Minimal research has examined utility of PC-PTSD-5 in family members of frontline medical workers. The aims of our study were to develop and elucidate the psychometric properties of the Chinese version of the PC-PTSD-5 and to determine its usefulness in screening for possible PTSD in relatives of Chinese healthcare workers during the COVID-19. Methods: We conducted a cross-sectional research in the relatives of medical staffs working in a general hospital during the COVID-19. Descriptive analysis was used to characterize demographic information of family members to find factors associated with PTSD symptoms. For reliability test, the internal consistency of PC-PTSD-5 was accessed using Cronbach's alpha coefficient. A validity test was assessed by Pearson's correlation between scales. A receiver operating characteristic (ROC) curve was used to evaluate the optimal cutoff score with the maximum Youden Index in this study. Results: The result of demographic information indicated that gender and the type of work undertaken by medical staff in the family have a potential impact on the PTSD symptoms of medical staff's family members. Cronbach's alpha coefficient of PC-PTSD-5 was 0.83, indicating the high reliability. Good validity was also demonstrated by Pearson coefficient. By calculating the Youden index, a cutoff score of 2 was found to be optimal in our study, with sensitivity of 80.74% and specificity of 88.43%. Conclusions: Our study has demonstrated the robust psychometric strengths of the PC-PTSD-5, introducing a reliable tool for screening PTSD among vulnerable and neglected families of these medical workers.

17.
Virus Res ; 305: 198553, 2021 11.
Article in English | MEDLINE | ID: covidwho-1386720

ABSTRACT

COVID-19 is seriously threatening human health all over the world. A comprehensive understanding of the genetic mechanisms driving the rapid evolution of its pathogen (SARS-CoV-2) is the key to controlling this pandemic. In this study, by comparing the entire genome sequences of SARS-CoV-2 isolates from Asia, Europe and America, and analyzing their phylogenetic histories, we found a lineage derived from a recombination event that likely occurred before March 2020. More importantly, the recombinant offspring has become the dominant strain responsible for more than one-third of the global cases in the pandemic. These results indicated that the recombination might have played a key role in the pandemic of the virus.


Subject(s)
COVID-19/epidemiology , Evolution, Molecular , Genome, Viral , Homologous Recombination , Mosaicism , SARS-CoV-2/genetics , Americas/epidemiology , Asia/epidemiology , Base Sequence , COVID-19/history , COVID-19/transmission , COVID-19/virology , Europe/epidemiology , Genomics/methods , History, 21st Century , Humans , Mutation , Phylogeny , SARS-CoV-2/classification , SARS-CoV-2/pathogenicity
18.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.08.03.21261544

ABSTRACT

ImportanceWhether herd immunity through mass vaccination is sufficient to curb SARS-CoV-2 transmission requires an understanding of the duration of vaccine-induced immunity, and the necessity and timing of booster doses. Objective: To evaluate immune persistence of two priming doses of CoronaVac, and immunogenicity and safety of a third dose in healthy adults [≥]60 years. Design, setting, and participants: We conducted a vaccine booster study built on a single-center, randomized, double-blind phase 1/2 trial of the two-dose schedule of CoronaVac among healthy adults[≥]60 years in Hebei, China. We examined neutralizing antibody titres six months or more after the second dose in all participants. We provided a third dose to 303 participants recruited in phase 2 trial to assess their immune responses. InterventionsTwo formulations (3 g, and 6 g) were used in phase 1 trial, and an additional formulation of 1.5 g was used in phase 2 trial. All participants were given two doses 28 days apart and followed up 6 months after the second dose. Participants in phase 2 received a third dose 8 months after the second dose. Main outcomes and measuresGeometric mean titres (GMT) of neutralizing antibodies to live SARS-CoV-2 and adverse events were assessed at multiple time points following vaccination. ResultsNeutralizing antibody titres dropped below the seropositive cutoff of 8 at 6 months after the primary vaccination in all vaccine groups in the phase 1/2 trial. A third dose given 8 months or more after the second dose significantly increased neutralizing antibody levels. In the 3 g group (the licensed formulation), GMT increased to 305 [95%CI 215.3-432.0] on day 7 following the third dose, an approximately 7-fold increase compared with the GMT 28 days after the second dose. All solicited adverse reactions reported within 28 days after a booster dose were of grade 1 or 2 severity. Conclusion and relevanceNeutralizing antibody titres declined substantially six months after two doses of CoronaVac among older adults. A booster dose rapidly induces robust immune responses. This evidence could help policymakers determine the necessity and the timing of a booster dose for older adults. Trial registrationClinicalTrials.gov (NCT04383574).

19.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.07.23.21261013

ABSTRACT

To allow a return to a pre-COVID-19 lifestyle, virtually every country has initiated a vaccination program to mitigate severe disease burden and control transmission; over 3.6 billion vaccine doses have been administered as of July 2021. However, it remains to be seen whether herd immunity will be within reach of these programs, especially as more transmissible SARS-CoV-2 variants continue to emerge. To address this question, we developed a data-driven model of SARS-CoV-2 transmission for Shanghai, China, a population with low prior immunity from natural infection. We found that extending the vaccination program to individuals aged 3-17 years plays a key role to reach herd immunity for the original SARS-CoV-2 lineages. With a vaccine efficacy 74% against infection, vaccine-induced herd immunity would require coverages of 93% or higher. Herd immunity for new variants, such as Alpha or Delta, can only be achieved with more efficacious vaccines and coverages above 80-90%. A continuation of the current pace of vaccination in China would reach 72% coverage by September 2021; although this program would fail to reach herd immunity it would reduce deaths by 95-100% in case of an outbreak. Efforts should be taken to increase population's confidence and willingness to be vaccinated and to guarantee highly efficacious vaccines against more transmissible variants of concern.


Subject(s)
COVID-19
20.
Clin Nephrol ; 96(4): 207-215, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1302710

ABSTRACT

BACKGROUND: Continuous renal replacement therapy (CRRT) has become an important multiple organ support therapy and it is widely used in the intensive care unit (ICU). The aim of this study was to clarify the association between CRRT and 28-day mortality in critically ill coronavirus disease 2019 (-COVID-19) patients receiving mechanical ventilation. MATERIALS AND METHODS: 112 respiratory decompensated critically ill adult patients with COVID-19 admitted to a COVID-19-designated ICU were included in this retrospective cohort study. Data on demographic information, comorbidities, laboratory findings upon ICU admission, and clinical outcomes were collected. The Kaplan-Meier method and Cox proportional hazard model were applied to determine the potential risk factors associated with 28-day mortality. RESULTS: The median age was 65.7 years, 67.8% were males, and 58.9% patients had at least one comorbidity. The median scores of the Charlson Comorbidity Index and Sequential Organ Failure Assessment (SOFA) were 3 and 7, respectively. Acute kidney injury (AKI) occurred in 57 critically ill patients upon ICU admission; 43 patients were classified as stage 2 - 3 AKI, and 36 patients were treated with CRRT. Age > 65 years, high SOFA score, damaged cardiac function, poor nutrition, and severe infection were significantly associated with increased 28-day mortality. AKI patients receiving CRRT had lower 28-day mortality compared with those not receiving CRRT (HR = 0.35, 95% CI: 0.21 - 0.58, p < 0.001). Initiating CRRT within 72 hours after mechanical ventilation did not improve survival after CRRT initiation. CONCLUSION: AKI prevalence and 28-day mortality are high in critically ill patients with COVID-19 receiving mechanical ventilation. CRRT plays a part in decreasing the mortality of critically ill COVID-19 patients with AKI receiving mechanical ventilation.


Subject(s)
Acute Kidney Injury , COVID-19 , Continuous Renal Replacement Therapy , Acute Kidney Injury/diagnosis , Acute Kidney Injury/therapy , Aged , Critical Illness , Humans , Intensive Care Units , Male , Renal Replacement Therapy , Respiration, Artificial , Retrospective Studies , SARS-CoV-2
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