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1.
NPJ Vaccines ; 7(1): 62, 2022 Jun 23.
Article in English | MEDLINE | ID: covidwho-1900491

ABSTRACT

The interaction between the aluminum salt-based adjuvants and the antigen in the vaccine formulation is one of the determining factors affecting the immuno-potentiation effect of vaccines. However, it is not clear how the intrinsic properties of the adjuvants could affect this interaction, which limits to benefit the improvement of existing adjuvants and further formulation of new vaccines. Here, we engineered aluminum oxyhydroxide (AlOOH) nanorods and used a variety of antigens including hepatitis B surface antigen (HBsAg), SARS-CoV-2 spike protein receptor-binding domain (RBD), bovine serum albumin (BSA) and ovalbumin (OVA) to identify the key physicochemical properties of adjuvant that determine the antigen adsorption at the nano-bio interface between selected antigen and AlOOH nanorod adjuvant. By using various physicochemical and biophysical characterization methods, it was demonstrated that the surface hydroxyl contents of AlOOH nanorods affected the adsorptive strength of the antigen and their specific surface area determined the adsorptive capacity of the antigen. In addition, surface hydroxyl contents had an impact on the stability of the adsorbed antigen. By engineering the key intrinsic characteristics of aluminum-based adjuvants, the antigen adsorption behavior with the aluminum adjuvant could be regulated. This will facilitate the design of vaccine formulations to optimize the adsorption and stability of the antigen in vaccine.

2.
Adv Differ Equ ; 2020(1): 391, 2020.
Article in English | MEDLINE | ID: covidwho-1706509

ABSTRACT

According to the report presented by the World Health Organization, a new member of viruses, namely, coronavirus, shortly 2019-nCoV, which arised in Wuhan, China, on January 7, 2020, has been introduced to the literature. The main aim of this paper is investigating and finding the optimal values for better understanding the mathematical model of the transfer of 2019-nCoV from the reservoir to people. This model, named Bats-Hosts-Reservoir-People coronavirus (BHRPC) model, is based on bats as essential animal beings. By using a powerful numerical method we obtain simulations of its spreading under suitably chosen parameters. Whereas the obtained results show the effectiveness of the theoretical method considered for the governing system, the results also present much light on the dynamic behavior of the Bats-Hosts-Reservoir-People transmission network coronavirus model.

3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-317615

ABSTRACT

Background: The COVID-19 pandemic has caused tremendous impact on global health and economics. The impact in African countries has not been investigated through fitting epidemic model to the reported COVID-19 deaths. Method: We downloaded data for the twelve most-affected countries with the highest cumulative COVID-19 deaths to estimate the time-varying effective reproduction number (B) and infection attack rate (IAR). We developed a simple epidemic model and fitted the model to reported COVID-19 deaths in 12 African countries, using iterated filtering and allowing flexible transmission rate. Results: : We found high heterogeneity in the case-fatality rate across countries, which may be due to different reporting or testing efforts. We found that South Africa, Tunisia, and Libya were hit hardest with a relatively higher a and infection attack rate Conclusion: To effectively control the spread of COVID-19 epidemics in Africa, there is a need to consider other mitigation strategies (such as improvement in socio-economic wellbeing, health care system, water supply, awareness campaigns).

4.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-324307

ABSTRACT

Background: Cardiovascular disease (CVD), one of the most common comorbidities of coronavirus disease 2019 (COVID-19), has been suspected to be associated with adverse outcomes in COVID-19 patients, but their correlation remains controversial. Method This is a quantitative meta-analysis on the basis of adjusted effect estimates. PubMed, Web of Science, MedRxiv, Scopus, Elsevier ScienceDirect, Cochrane Library and EMBASE were searched comprehensively to obtain a complete data source up to January 7, 2021. Pooled effects (hazard ratio (HR), odds ratio (OR)) and the 95% confidence intervals (CIs) were estimated to evaluate the risk of the adverse outcomes in COVID-19 patients with CVD. Heterogeneity was assessed by Cochran’s Q-statistic, I²test, and meta-regression. In addition, we also provided the prediction interval, which was helpful for assessing whether the variation across studies was clinically significant. The robustness of the results was evaluated by sensitivity analysis. Publication bias was assessed by Begg’s test, Egger’s test, and trim-and-fill method. Result Our results revealed that COVID-19 patients with pre-existing CVD tended more to adverse outcomes on the basis of 203 eligible studies with 24,033,838 cases (pooled ORs = 1.41, 95% CIs: 1.32–1.51, prediction interval: 0.84–2.39;pooled HRs = 1.34, 95% CIs: 1.23–1.46, prediction interval: 0.82–2.21). Further subgroup analyses stratified by age, the proportion of male, study design, disease types, sample size, region and disease outcomes also showed that pre-existing CVD was significantly associated with adverse outcomes among COVID-19 patients. Conclusion Our findings demonstrated that pre-existing CVD was an independent risk factor associated with adverse outcomes among COVID-19 patients.

5.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-321870

ABSTRACT

By February 2021, the overall impact of the COVID-19 pandemic in India had been relatively mild in terms of total reported cases and deaths. Surprisingly, the second wave in early April becomes devastating and attracts worldwide attention. On April 30, 2021, India became the first country reporting over 400,000 daily new cases. Multiple factors drove the rapid growth of the epidemic in India and caused a large number of deaths within a very short period. These factors include a new variant with increased transmissibility, a lack of preparations exists national wide, and health and safety precautions poorly implemented or enforced during festivals, sporting events, and state/local elections. Moreover, India's cases and deaths are vastly underreported due to poor infrastructure, and low testing rates. In this paper, we use the COVID-19 mortality data in India and a mathematical model to calculate the effective reproduction number and to model the wave pattern in India. We propose a new approach to forecast the epidemic size and peak timing in India with the aim to inform mitigation in India. Our model simulation matched the reported deaths accurately and is reasonably close to results of serological study. We forecast that the IAR could reach 43% by June 13, 2021 under the current trend, which means 532,629 reported deaths with a 95% CI (552,445, 513,194) ie., double the current total deaths. Our approach is readily applicable in other countries and with other type of data (e.g. excess deaths).

6.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-314769

ABSTRACT

Background: For Severe Acute Respiratory Syndrome Coronavirus-2, the investigation of the heterogeneity of individual infectiousness is important due to the recorded widespread cross reactive immunity of general population that can alter transmission dynamics. We therefore aimed to understand how SARS-COV-2 transmits in the general population in relation to age. Design: Using a sample of infected population with SARS-COV-2 in close geographical proximity to the initial Severe Advanced Respiratory Syndrome-1 (SARS-1) outbreak, we explored the association between infector’s age and dispersion (or heterogeneity) of individual infectiousness (k) in order to investigate the relatedness with the age of an individual’s capability to disperse SARS-COV-2. Results: We have found a negative association between k and increase of infector’s age. Significantly this becomes more evident for the age group of 20-60 years comparing with the infectors of younger age. Conclusions: Non pharmaceutical interventions can be effective to age group between 20-60 years whereas in youngsters and older patients containment of spreading must be made by other means to be effective. Immunity differences between age groups may reflect their differences in heterogeneity predicted by variance in dispersion parameter (k) .

7.
Cell Rep ; 37(11): 110112, 2021 12 14.
Article in English | MEDLINE | ID: covidwho-1530687

ABSTRACT

An ideal vaccine against SARS-CoV-2 is expected to elicit broad immunity to prevent viral infection and disease, with efficient viral clearance in the upper respiratory tract (URT). Here, the N protein and prefusion-full S protein (SFLmut) are combined with flagellin (KF) and cyclic GMP-AMP (cGAMP) to generate a candidate vaccine, and this vaccine elicits stronger systemic and mucosal humoral immunity than vaccines containing other forms of the S protein. Furthermore, the candidate vaccine administered via intranasal route can enhance local immune responses in the respiratory tract. Importantly, human ACE2 transgenic mice given the candidate vaccine are protected against lethal SARS-CoV-2 challenge, with superior protection in the URT compared with that in mice immunized with an inactivated vaccine. In summary, the developed vaccine can elicit a multifaceted immune response and induce robust viral clearance in the URT, which makes it a potential vaccine for preventing disease and infection of SARS-CoV-2.


Subject(s)
COVID-19 Vaccines/immunology , Combined Modality Therapy/methods , SARS-CoV-2/immunology , Administration, Intranasal , Angiotensin-Converting Enzyme 2/immunology , Angiotensin-Converting Enzyme 2/metabolism , Animals , Antibodies, Viral/immunology , Antigens/immunology , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/genetics , Chlorocebus aethiops , Coronavirus Nucleocapsid Proteins/immunology , Female , Flagellin/immunology , HEK293 Cells , Humans , Immunity/immunology , Immunity/physiology , Immunity, Humoral/immunology , Immunization , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nucleotides, Cyclic/immunology , Phosphoproteins/immunology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/immunology , Vaccination , Vero Cells
8.
BMC Public Health ; 21(1): 1533, 2021 08 11.
Article in English | MEDLINE | ID: covidwho-1477304

ABSTRACT

BACKGROUND: Cardiovascular disease (CVD), one of the most common comorbidities of coronavirus disease 2019 (COVID-19), has been suspected to be associated with adverse outcomes in COVID-19 patients, but their correlation remains controversial. METHOD: This is a quantitative meta-analysis on the basis of adjusted effect estimates. PubMed, Web of Science, MedRxiv, Scopus, Elsevier ScienceDirect, Cochrane Library and EMBASE were searched comprehensively to obtain a complete data source up to January 7, 2021. Pooled effects (hazard ratio (HR), odds ratio (OR)) and the 95% confidence intervals (CIs) were estimated to evaluate the risk of the adverse outcomes in COVID-19 patients with CVD. Heterogeneity was assessed by Cochran's Q-statistic, I2test, and meta-regression. In addition, we also provided the prediction interval, which was helpful for assessing whether the variation across studies was clinically significant. The robustness of the results was evaluated by sensitivity analysis. Publication bias was assessed by Begg's test, Egger's test, and trim-and-fill method. RESULT: Our results revealed that COVID-19 patients with pre-existing CVD tended more to adverse outcomes on the basis of 203 eligible studies with 24,032,712 cases (pooled ORs = 1.41, 95% CIs: 1.32-1.51, prediction interval: 0.84-2.39; pooled HRs = 1.34, 95% CIs: 1.23-1.46, prediction interval: 0.82-2.21). Further subgroup analyses stratified by age, the proportion of males, study design, disease types, sample size, region and disease outcomes also showed that pre-existing CVD was significantly associated with adverse outcomes among COVID-19 patients. CONCLUSION: Our findings demonstrated that pre-existing CVD was an independent risk factor associated with adverse outcomes among COVID-19 patients.


Subject(s)
COVID-19 , Cardiovascular Diseases , Cardiovascular Diseases/epidemiology , Comorbidity , Humans , Male , Risk Factors , SARS-CoV-2
10.
Front Pharmacol ; 12: 708636, 2021.
Article in English | MEDLINE | ID: covidwho-1450831

ABSTRACT

Background: The outbreak of coronavirus disease 2019 (COVID-19) has rapidly spread to become a global emergency since December 2019. Chinese herbal medicine plays an important role in the treatment of COVID-19. Chinese herbal medicine honeysuckle is an extremely used traditional edible and medicinal herb. Many trials suggest that honeysuckle has obtained a good curative effect for COVID-19; however, no systematic evaluation on the clinical efficacy of honeysuckle in the treatment of COVID-19 is reported. This study aimed to evaluate the efficacy and safety of Chinese herbal medicine honeysuckle in the treatment of COVID-19. Methods: Seven electronic databases (PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, Wanfang Database, and China Biology Medicine) were searched to identify randomized controlled trials (RCTs) of honeysuckle for adult patients (aged ≥ 18 years) with COVID-19. The Cochrane Risk of Bias Tool was applied to assess the methodological quality of trials. Review Manager 5.3 software was used for data analysis. Results: Overall, nine RCTs involving 1,286 patients were enrolled. Our meta-analyses found that combination therapy of honeysuckle and conventional therapy was more effective than conventional therapy alone in lung computed tomography (CT) [relative risk (RR) = 1.24, 95% confidence interval (95%CI) (1.12, 1.37), P < 0.0001], clinical cure rate [RR = 1.21, 95%CI (1.12, 1.31), P < 0.00001], and rate of conversion to severe cases [RR = 0.50, 95%CI (0.33, 0.76), P = 0.001]. Besides, combination therapy can improve the symptom score of fever, cough reduction rate, symptom score of cough, and inflammatory biomarkers (white blood cell (WBC) count; C-reactive protein (CRP)) (P < 0.05). Conclusion: Honeysuckle combined with conventional therapy may be beneficial for the treatment of COVID-19 in improving lung CT, clinical cure rate, clinical symptoms, and laboratory indicators and reducing the rate of conversion to severe cases. Besides, combination therapy did not increase adverse drug events. More high-quality RCTs are needed in the future.

11.
Covid-19 in Asia: Law and Policy Contexts ; : 207-220, 2021.
Article in English | Scopus | ID: covidwho-1370799

ABSTRACT

This chapter assesses whether the short-term benefits of using digital technology to suppress the Covid-19 pandemic justify the detrimental long-term consequences for privacy. It addresses this complex question through an inevitably incomplete discussion of privacy data protection laws, technology design, and trust in governments and technology providers as well as cultural understandings of privacy. After outlining the technology-assisted measures in various regions in Asia, the chapter highlights major privacy concerns and looks at a number of trade-offs that emerge from the use of technology to contain the spread of the virus. These trade-offs exemplify the risks of adoption of just-in-time software technologies for public health purposes without fully understanding their impact on users and of potentially erroneous data-driven decisions and the involuntary collection of personal data. They also raise important policy questions in the dynamic and fast-shifting context of the Covid-19 pandemic. © the several contributors 2021.

13.
Nicotine Tob Res ; 23(11): 1947-1951, 2021 10 07.
Article in English | MEDLINE | ID: covidwho-1246745

ABSTRACT

INTRODUCTION: Smoking can cause mucociliary clearing dysfunction and poor pulmonary immunity, leading to more severe infection. We performed this study to explore the association between smoking and mortality of coronavirus disease 2019 (COVID-19) patients utilizing a quantitative meta-analysis on the basis of adjusted effect estimates. AIMS AND METHODS: We conducted a systematic search of the online databases including PubMed, Web of Science, Scopus, and Embase. Only articles reporting adjusted effect estimates on the association between smoking and the risk of mortality among COVID-19 patients in English were included. Newcastle-Ottawa scale was fitted to assess the risk of bias. A random-effects model was applied to calculate the pooled effect with the corresponding 95% confidence interval (CI). RESULTS: A total of 73 articles with 863 313 COVID-19 patients were included in this meta-analysis. Our results indicated that smoking was significantly associated with an increased risk for death in patients with COVID-19 (pooled relative risk = 1.19, 95% CI = 1.12-1.27). Sensitivity analysis indicated that our results were stable and robust. CONCLUSIONS: Smoking was independently associated with an increased risk for mortality in COVID-19 patients. IMPLICATIONS: This present study may contribute to summarizing the association between smoking and the risk of COVID-19 mortality based on adjusted effect estimates. More detailed and complete data on smoking status should be collected to more accurately estimate the effect of smoking on COVID-19 mortality.


Subject(s)
COVID-19/mortality , Tobacco Smoking/adverse effects , Humans , Risk
14.
Arch Med Res ; 52(7): 755-760, 2021 10.
Article in English | MEDLINE | ID: covidwho-1240192

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by a novel virus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has brought new challenges for global health systems. OBJECTIVE: The objective of this study was to investigate whether pre-diagnosed cancer was an independent risk factor for fatal outcomes of coronavirus disease 2019 (COVID-19) patients. METHOD: A comprehensive search was conducted in major databases of PubMed, Web of Science, and EMBASE to identify all published full-text studies as of January 20, 2021. Inter-study heterogeneity was assessed using Cochran's Q-statistic and I² test. A meta-analysis of random- or fixed-effects model was used to estimate the effect size. Publication bias, sensitivity analysis and subgroup analysis were also carried out. RESULTS: The confounders-adjusted pooled effects (pooled odds ratio [OR] = 1.47, 95% confidence interval [CI]: 1.31-1.65; pooled hazard ratio [HR] = 1.37, 95% CI: 1.21-1.54) indicated that COVID-19 patients with pre-diagnosed cancer were more likely to progress to fatal outcomes based on 96 articles with 6,518,992 COVID-19 patients. Further subgroup analyses by age, sample size, the proportion of males, region, study design and quality rating exhibited consistent findings with the overall effect size. CONCLUSION: Our analysis provides the objective findings based on the adjusted effect estimates that pre-diagnosed cancer is an independent risk factor for fatal outcome of COVID-19 patients. During the current COVID-19 pandemic, health workers should pay particular attention to cancer care for cancer patients and should prioritize cancer patients for vaccination.


Subject(s)
COVID-19 , Neoplasms , Humans , Male , Neoplasms/epidemiology , Pandemics , Risk Factors , SARS-CoV-2
15.
Emerging Markets, Finance & Trade ; 57(6):1689-1698, 2021.
Article in English | ProQuest Central | ID: covidwho-1219882

ABSTRACT

Using stock market data from six emerging economies (that is, China, Brazil, India, Malaysia, the Philippines, and Russia), we find that analysts’ forecast revision, a significant anomaly in emerging markets during the past two decades, is disappeared during the COVID-19 pandemic. We formulate factor sorted portfolio and Fama–MacBeth regression to explain the disappearance. We find that the return predictability of analysts’ forecast revision is negatively correlated with the pandemic’s severity, whereas analysts have not provided sufficient information to investors under this severe pandemic. We supplement the theory of time-varying risk premium as well as sophisticated investors with fresh evidence.

16.
Clin Infect Dis ; 71(16): 2158-2166, 2020 11 19.
Article in English | MEDLINE | ID: covidwho-1153176

ABSTRACT

BACKGROUND: In December 2019, the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) broke out in Wuhan. Epidemiological and clinical characteristics of patients with COVID-19 have been reported, but the relationships between laboratory features and viral load has not been comprehensively described. METHODS: Adult inpatients (≥18 years old) with COVID-19 who underwent multiple (≥5 times) nucleic acid tests with nasal and pharyngeal swabs were recruited from Renmin Hospital of Wuhan University, including general patients (n = 70), severe patients (n = 195), and critical patients (n = 43). Laboratory data, demographic data, and clinical data were extracted from electronic medical records. The fitted polynomial curve was used to explore the association between serial viral loads and illness severity. RESULTS: Viral load of SARS-CoV-2 peaked within the first few days (2-4 days) after admission, then decreased rapidly along with virus rebound under treatment. Critical patients had the highest viral loads, in contrast to the general patients showing the lowest viral loads. The viral loads were higher in sputum compared with nasal and pharyngeal swab (P = .026). The positive rate of respiratory tract samples was significantly higher than that of gastrointestinal tract samples (P < .001). The SARS-CoV-2 viral load was negatively correlated with portion parameters of blood routine and lymphocyte subsets and was positively associated with laboratory features of cardiovascular system. CONCLUSIONS: The serial viral loads of patients revealed whole viral shedding during hospitalization and the resurgence of virus during the treatment, which could be used for early warning of illness severity, thus improve antiviral interventions.


Subject(s)
COVID-19/epidemiology , Coronavirus/pathogenicity , China/epidemiology , Female , Humans , Male , Serologic Tests , Viral Load
17.
Ann Allergy Asthma Immunol ; 126(5): 524-534, 2021 05.
Article in English | MEDLINE | ID: covidwho-1086748

ABSTRACT

BACKGROUND: It is unclear whether asthma has an influence on contracting coronavirus disease 2019 (COVID-19) or having worse outcomes from COVID-19 disease. OBJECTIVE: To explore the prevalence of asthma in patients with COVID-19 and the relationship between asthma and patients with COVID-19 with poor outcomes. METHODS: The pooled prevalence of asthma in patients with COVID-19 and corresponding 95% confidence interval (CI) were estimated. The pooled effect size (ES) was used to evaluate the association between asthma and patients with COVID-19 with poor outcomes. RESULTS: The pooled prevalence of asthma in patients with COVID-19 worldwide was 8.3% (95% CI, 7.6-9.0) based on 116 articles (119 studies) with 403,392 cases. The pooled ES based on unadjusted effect estimates revealed that asthma was not associated with reduced risk of poor outcomes in patients with COVID-19 (ES, 0.91; 95% CI, 0.78-1.06). Similarly, the pooled ES based on unadjusted effect estimates revealed that asthma was not associated with the reduced risk of mortality in patients with COVID-19 (ES, 0.88; 95% CI, 0.73-1.05). However, the pooled ES based on adjusted effect estimates indicated that asthma was significantly associated with reduced risk of mortality in patients with COVID-19 (ES 0.80, 95% CI 0.74-0.86). CONCLUSION: The pooled prevalence of asthma in patients with COVID-19 was similar to that in the general population, and asthma might be an independent protective factor for the death of patients with COVID-19, which suggests that we should pay high attention to patients co-infected asthma and COVID-19 and take locally tailored interventions and treatment. Further well-designed studies with large sample sizes are required to verify our findings.


Subject(s)
Asthma/epidemiology , COVID-19/epidemiology , COVID-19/mortality , Coinfection/epidemiology , Asthma/complications , COVID-19/pathology , Coinfection/mortality , Coinfection/pathology , Humans , SARS-CoV-2 , Treatment Outcome
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