Response and duration of serum anti-SARS-CoV-2 antibodies induced by the third dose of an inactivated vaccine: A prospective longitudinal cohort study at 21 serial time points over 641 days.

Given the prevalence of low-pathogenic but highly infectious Omicron variants, a cohort study was conducted to assess the response and duration of novel coronavirus-inactivated vaccine-induced antibodies 1 year after the third dose (Day 641). Blood samples were collected and anti-spike neutralizing antibodies (neutralizing antibody), total antibodies against the receptor-binding domain of the spike protein (total antibody), and immunoglobulin G antibodies against the spike protein (IgG antibody) were determined. Antibody kinetics and attenuation were evaluated. The results showed that the levels of neutralizing, total, and IgG antibodies on Day 641 were 98.05 IU/mL, 152.8 AU/mL, and 7.68 S/CO, respectively. Levels of anti-SARS-CoV-2 antibodies were higher in the younger subgroup than in the older subgroup at several time points after the second and third doses. The seropositive rate of neutralizing antibodies providing protection from infection or severe infection was 46.87% and 87.5%, and the seropositive rates of total antibody and IgG antibody were maintained at 100% and 90.63%, respectively. The half-lives of neutralizing, total, and IgG antibodies were 186.89, 363.04, and 417.50 days, respectively. Collectively, anti-SARS-CoV-2 antibodies may provide a certain degree of protection from infection 1 year after the third dose and high protection from severe infection.

The causal relationship between COVID-19 and increased intraocular pressure: A bidirectional two-sample Mendelian randomization study.

Background: Coronavirus disease 2019 (COVID-19) has brought great challenges to the global public health system and huge economic burdens to society, the causal effect of COVID-19 and intraocular pressure was blank. Objective: This study aimed to explore the causal association between coronavirus disease (COVID-19) susceptibility, severity and criticality and intraocular pressure (IOP) by bidirectional Mendelian randomization (MR) analysis. Materials and methods: Genetic associations with COVID-19 susceptibility, severity and criticality were obtained from the COVID-19 Host Genetics Initiative. Genetic associations with IOP were obtained from GWAS summary data. The standard inverse variance weighted (IVW) method was used in the primary assessment of this causality. Other methods were also implemented in supplementary analyses. Finally, sensitivity analysis was performed to evaluate the reliability and stability of the results. Results: The results showed that COVID-19 susceptibility had null effect on IOP (ß = 0.131; Se = 0.211; P = 0.533) as assessed by the IVW method. Moreover, the results revealed that COVID-19 severity, specifically, hospitalization due to COVID-19, had a positive effect on IOP with nominal significance (ß = 0.228; Se = 0.116; P = 0.049). However, there were null effect of COVID-19 criticality on IOP (ß = 0.078; Se = 0.065; P = 0.227). Sensitivity analysis showed that all the results were reliable and stable. The reverse MR analysis revealed that there was null effect of IOP on COVID-19. Conclusions: We demonstrated that hospitalization due to COVID-19 might increase IOP; therefore, greater attention should be given to monitoring IOP in inpatients with COVID-19.

Development and Evaluation of a Novel One-Step RT-qPCR Targeting the Vero Gene for the Identification of False-Positive Results Caused by Inactivated Virus Vaccine Contamination.

To identify false-positive SARS-CoV-2 test results caused by novel coronavirus inactivated vaccine contamination, a novel RT-qPCR targeting the ORF1ab and N genes of SARS-CoV-2 and Vero gene was developed. The amplification efficiency, precision, and lower limit of detection (LLOD) of the RT-qPCR assay were determined. A total of 346 clinical samples and 132 environmental samples were assessed, and the diagnostic performance was evaluated. The results showed that the amplification efficiency of the ORF1ab, N, and Vero genes was 95%, 97%, and 93%, respectively. The coefficients of variation of Ct values at a concentration of 3 × 104 copies/mL were lower than 5%. The LLOD for the ORF1ab, N, and Vero genes reached 8.0, 3.3, and 8.2 copies/reaction, respectively. For the 346 clinical samples, our RT-qPCR assay identified SARS-CoV-2-positive and SARS-CoV-2-negative samples with a sensitivity of 100.00% and a specificity of 99.30% and novel coronavirus inactivated vaccine-contaminated samples with a sensitivity of 100% and a specificity of 100%. For the environmental samples, our RT-qPCR assay identified novel coronavirus inactivated vaccine-contaminated samples with a sensitivity of 88.06% and a specificity of 95.38%. In conclusion, the RT-qPCR assay we established can be used to diagnose COVID-19 and, to a certain extent, false-positive results due to vaccine contamination.

Anti-SARS-CoV-2 IgM Secondary Response Was Suppressed by Preexisting Immunity in Vaccinees: A Prospective, Longitudinal Cohort Study over 456 Days.

To obtain more insight into IgM in anti-SARS-CoV-2 immunity a prospective cohort study was carried out in 32 volunteers to longitudinally profile the kinetics of the anti-SARS-CoV-2 IgM response induced by administration of a three-dose inactivated SARS-CoV-2 vaccine regimen at 19 serial time points over 456 days. The first and second doses were considered primary immunization, while the third dose was considered secondary immunization. IgM antibodies showed a low secondary response that was different from the other three antibodies (neutralizing, total, and IgG antibodies). There were 31.25% (10/32) (95% CI, 14.30-48.20%) of participants who never achieved a positive IgM antibody conversion over 456 days after vaccination. The seropositivity rate of IgM antibodies was 68.75% (22/32) (95% CI, 51.80-85.70%) after primary immunization. Unexpectedly, after secondary immunization the seropositivity response rate was only 9.38% (3/32) (95% CI, 1.30-20.10%), which was much lower than that after primary immunization (p = 0.000). Spearman's correlation analysis indicated a poor correlation of IgM antibodies with the other three antibodies. IgM response in vaccinees was completely different from the response patterns of neutralizing, total, and IgG antibodies following both the primary immunization and the secondary immunization and was suppressed by pre-existing immunity induced by primary immunization.

Evaluation of the efficacy of four anti-SARS-CoV-2 antibodies after vaccination using kits from two manufacturers: A prospective, longitudinal, cohort study at 11 serial time points within 160 days.

PURPOSE: The accuracy of level of anti- severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies is a great concern. We aimed to compare the efficacy of anti-SARS-CoV-2 antibody detection kits from two manufacturers in evaluating the efficacy of SARS-CoV-2 vaccines. METHODS: The immune responses and consistency of four anti-SARS-CoV-2 antibodies were evaluated using two manufacturers' antibody kits (A and B) in 61 subjects within 160 days after vaccination with the CoronaVac vaccine. RESULTS: The total seropositivity rates of neutralizing antibodies and IgM antibodies detected by kit A were higher than those detected by kit B (P = 0.003 and P < 0.001, respectively). Conversely, the total seropositivity rates of total antibodies and IgG antibodies were higher in kit B than kit A (P < 0.001 and P < 0.001, respectively). The consistency rates showed less than 90% agreement between the kits for the detection of the four antibodies, and the κ score showed moderate or substantial consistency. The half-lives of neutralizing antibodies, total antibodies, and IgG antibodies within 160 days after vaccination, detected by kit A were 63.88 days, 80.50 days, and 63.70 days, respectively and by kit B were 97.06 days, 65.41 days, and 77.99 days, respectively. CONCLUSION: The efficacy of antibody detection differed between the two commercial anti-SARS-CoV-2 antibody kits, although there was moderate consistency, which may affect the clinical application and formulation of the vaccine strategy.

Incidence of childhood cancer in Canada during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic has had a major impact on access to health care resources. Our objective was to estimate the impact of the COVID-19 pandemic on the incidence of childhood cancer in Canada. We also aimed to compare the proportion of patients who enrolled in clinical trials at diagnosis, presented with metastatic disease or had an early death during the first 9 months of the COVID-19 pandemic compared with previous years. METHODS: We conducted an observational study that included children younger than 15 years with a new diagnosis of cancer between March 2016 and November 2020 at 1 of 17 Canadian pediatric oncology centres. Our primary outcome was the monthly age-standardized incidence rates (ASIRs) of cancers. We evaluated level and trend changes using interventional autoregressive integrated moving average models. Secondary outcomes were the proportion of patients who were enrolled in a clinical trial, who had metastatic or advanced disease and who died within 30 days. We compared the baseline and pandemic periods using rate ratios (RRs) and 95% confidence intervals (CIs). RESULTS: Age-standardized incidence rates during COVID-19 quarters were 157.7, 164.6, and 148.0 per million, respectively, whereas quarterly baseline ASIRs ranged between 150.3 and 175.1 per million (incidence RR 0.93 [95% CI 0.78 to 1.12] to incidence RR 1.04 [95% CI 0.87 to 1.24]). We found no statistically significant level or slope changes between the projected and observed ASIRs for all new cancers (parameter estimate [ß], level 4.98, 95% CI -15.1 to 25.04, p = 0.25), or when stratified by cancer type or by geographic area. Clinical trial enrolment rate was stable or increased during the pandemic compared with baseline (RR 1.22 [95% CI 0.70 to 2.13] to RR 1.71 [95% CI 1.01 to 2.89]). There was no difference in the proportion of patients with metastatic disease (RR 0.84 [95% CI 0.55 to 1.29] to RR 1.22 [0.84 to 1.79]), or who died within 30 days (RR 0.16 [95% CI 0.01 to 3.04] to RR 1.73 [95% CI 0.38 to 15.2]). INTERPRETATION: We did not observe a statistically significant change in the incidence of childhood cancer, or in the proportion of children enrolling in a clinical trial, presenting with metastatic disease or who died early during the first 9 months of the COVID-19 pandemic, which suggests that access to health care in pediatric oncology was not reduced substantially in Canada.

How to Reach a Regional Cooperation Mechanism to Deal With the Epidemic: An Analysis From the Game Theory Perspective.

The outbreak and persistence of COVID-19 have posed a great threat to global public health and economic development. The continuous economic deterioration has been intensified due to the continuous prevention and control measures, such as closed management. Insisting on the prevention of the epidemic or economic restart has become a dilemma for all countries. Epidemic prevention is not only the main behavior of a single country but also a common problem faced by all countries in the region. Continuous prevention measures will affect economic development, but an early restart of the economy is faced with the recurrence of the epidemic. To avoid the emergence of prisoner's dilemma in the governance of the epidemic, each country cannot make decisions with its optimization, and so it is necessary to build a regional cooperation mechanism to achieve the overall optimization of the economy and prevent the epidemic. Based on the game theory, we analyzed the behavior of countries when carrying out regional cooperation to govern the epidemic and put forward specific cooperative income distribution schemes according to the different attributes of the countries. Our results showed that in the presence of population mobility, regional cooperation to govern the epidemic can minimize the total number of infected people and maximize the overall utility of the region, which was significantly better than the overall benefits of the region in the case of non-cooperation. However, in detail, the smaller the difference of preference for preventing and controlling the epidemic between the two, the more likely it is to lead to a win-win situation. Otherwise, there will be one with damaged interests. When damaged interests appear, the appropriate distribution of cooperative income to the country with a small economic scale and low preference in preventing the epidemic is more conducive to the achievement of cooperative mechanisms and the realization of a win-win situation in the region.

Emotional states and coping methods in nursing and non-nursing students responding to COVID-19: a cross-sectional study in China.

OBJECTIVES: To evaluate the emotion, coping strategy, dealing methods and their correlation in the COVID-19 outbreak among nursing and non-nursing students. DESIGN AND SETTING: A cross-sectional online survey. PARTICIPANTS: Full-time nursing and non-nursing undergraduate students. MAIN OUTCOME MEASURE: The Generalized Anxiety Disorder 7 (GAD-7) and Patient Health Questionnaire-9 (PHQ-9) were used to determine the emotional status in the COVID-19 pandemic among nursing and non-nursing students. Emotion Regulation Questionnaire (ERQ) was used to measure the emotion regulation strategies and the Simplified Coping Style Questionnaire (SCSQ) was used to evaluate the coping methods among nursing and non-nursing students. RESULTS: In total, 746 students including 366 nursing students and 380 non-nursing students participated in the survey. Compared with the non-nursing students, a significant decrease was noticed in GAD-7 score (p<0.01) and PHQ-9 (p<0.01) in the nursing students. The cognition re-evaluation score in the nursing students was significantly lower than that of the non-nursing students (p<0.05). In the nursing students, the score of anxiety was positively correlated with ERQ expression inhibition (p<0.01) and SCSQ negative coping (p<0.01), while the score of depression was also positively correlated with ERQ expression inhibition (p<0.01) and SCSQ negative coping (p<0.01). There was a negative correlation between SCSQ and the scores of anxiety (p<0.05) and depression (p<0.05). In the non-nursing students, the anxiety score was positively correlated with the SCSQ negative coping (p<0.01), while the depression score was positively correlated with the ERQ expression inhibition (p<0.01) and SCSQ negative coping (p<0.01). CONCLUSIONS: COVID-19 affected the emotional status of nursing and non-nursing students. The emotional status was correlated with the emotional regulation and coping methods. Staff involved in the nursing professionals should pay attention to the psychological status of the nursing and non-nursing students, and give moderate psychological interference in the presence of COVID-19.

Research on International Cooperative Governance of the COVID-19.

Since the first case of the novel coronavirus (SARS-CoV-2) was reported in Wuhan, China, in December 2019, the coronavirus disease (COVID-19) has quickly spread to all the corners of the world. Amid the global public health threats posed by the COVID-19 pandemic, active cooperative governance has gradually emerged as the most powerful weapon against its spread. To facilitate international cooperation for pandemic governance, this paper applied the evolutionary game theory to analyze the factors influencing active cooperative governance and, based on the results, proposed a series of recommendations for promoting international cooperation. (1) leveraging the role of international organizations to reduce the cost of realizing the strategy of active cooperative governance, (2) promoting the international exchange of related experiences to lower the cost of active pandemic governance, (3) sustaining productive and daily activities during the pandemic in a classified and hierarchical manner to reduce the economic loss incurred by active pandemic governance, and (4) optimizing the incentive measures of international organizations to facilitate the selection of active cooperative governance. Finally, from the four aspects of resource management of pandemic treatment, supply management of living materials, population flow cooperation management, and governance fund cooperation management, this paper gives the path of international pandemic cooperative governance.

Population migration, spread of COVID-19, and epidemic prevention and control: empirical evidence from China.

BACKGROUND: This study applied the susceptible-exposed-infectious-removed (SEIR) model to analyze and simulate the transmission mechanisms of the coronavirus disease 2019 (COVID-19) in China. METHODS: The population migration was embedded in the SEIR model to simulate and analyze the effects of the amount of population inflow on the number of confirmed cases. Based on numerical simulations, this study used statistical data for the empirical validation of its theoretical deductions and discussed how to improve the effectiveness of epidemic prevention and control considering population migration variables. Statistics regarding the numbers of infected people in various provinces were obtained from the epidemic-related data reported by China's National Health Commission. RESULTS: This study explored how the epidemic should be prevented and controlled from the perspective of population migration variables. It found that the combination of a susceptible population, an infected population, and transmission media were important routes affecting the number of infections and that the migration of a Hubei-related infected population played a key role in promoting epidemic spread. Epidemic prevention and control should focus on regions with better economic conditions than the epidemic region. Prevention and control efforts should focus on the more populated neighboring provinces having convenient transportation links with the epidemic region. To prevent and control epidemic spread, priority should be given to elucidating the destinations and directions of population migration from the domestic origin of infections, and then controlling population migration or human-to-human contact after such migration. CONCLUSIONS: This study enriched and expanded on simulations of the effects of population migration on the COVID-19 epidemic and China-based empirical studies while offering an epidemic evaluation and warning mechanism to prevent and control similar public health emergencies in the future.

Medical resources and coronavirus disease (COVID-19) mortality rate: Evidence and implications from Hubei province in China.

In light of the ongoing coronavirus disease (COVID-19) pandemic, this study aims to examine the relationship between the availability of public health resources and the mortality rate of this disease. We conducted empirical analyses using linear regression, a time-varying effect model, and a regression discontinuity design to investigate the association of medical resources with the mortality rate of the COVID-19 patients in Hubei, China. The results showed that the numbers of hospital beds, healthcare system beds, and medical staff per confirmed cases all had significant negative effects on the coronavirus disease mortality rate. Furthermore, in the context of the severe pandemic currently being experienced worldwide, the present study summarized the experience and implications in pandemic prevention and control in Hubei province from the perspective of medical resource integration as follows: First, hospitals' internal medical resources were integrated, breaking interdepartmental barriers. Second, joint pandemic control was realized by integrating regional healthcare system resources. Finally, an external medical resource allocation system was developed.

Population migration, confirmed COVID-19 cases, pandemic prevention, and control: evidence and experiences from China.

Aim: The virulence of the novel coronavirus disease (COVID-19) has facilitated its rapid transition towards becoming a pandemic. Hence, this study aims to investigate the association between population migration and the number of confirmed COVID-19 cases in China while investigating its measures for pandemic prevention and control. Subject and methods: A susceptible-exposed-infected-recovered-dormancy (SEIRD) model for the spread of COVID-19 in China was created to theoretically simulate the relationship between the populations migrating from Wuhan and the number of confirmed cases. Data from Baidu's real-time dynamic pandemic monitoring system were elicited to empirically examine the theoretical inferences. Results: Populations migrating from Wuhan to other cities increased the initial number of latently infected cases in these cities, raising the number of confirmed cases. Hence, implementing social distancing between the susceptible and infected populations could effectively lower the number of infected cases. Using data from Baidu's real-time dynamic pandemic monitoring system, the empirical results revealed that an increase of 1000 persons migrating from Wuhan raised the number of confirmed cases by 4.82 persons. Conclusion: This study confirmed the positive association between population migration and the number of confirmed COVID-19 cases. Based on the theoretical and empirical analysis, China's pandemic prevention and control measures are discussed.

The immediate psychological effects of Coronavirus Disease 2019 on medical and non-medical students in China.

OBJECTIVES: To investigate the immediate psychological effects of Coronavirus Disease 2019 (COVID-19) on medical and non-medical students. METHODS: An online survey of 805 medical students and 1900 non-medical students was conducted from Feb 4, 2020 to Feb 7, 2020, in China. The questionnaire measured the subjective estimated severity of COVID-19, the impact of the outbreak, and the levels of anxiety and depression of both medical and non-medical students. RESULTS: Medical students estimated COVID-19 to be more serious and disastrous than non-medical students, while they scored lower than non-medical students on the Impact of Event Scale-Revised (IES-R), and less severe anxiety and depression than non-medical students. The students experienced greater impact from the outbreak and a higher rate of anxiety and depression with increased time focusing on the outbreak. The difference in psychological effects between medical and non-medical students was further enlarged when focusing time was prolonged. CONCLUSIONS: The immediate psychological effects of COVID-19 on medical and non-medical students exhibit different characteristics. The outcome of this study provides implication that providing accurate and transparent information about the epidemic and appropriate COVID-19-based knowledge in accessible ways will contribute to the public's mental health during the outbreak.