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1.
Infect Dis Poverty ; 11(1): 32, 2022 Mar 18.
Article in English | MEDLINE | ID: covidwho-1833357

ABSTRACT

BACKGROUND: Nucleic acid test (NAT) could effectively control the spread of COVID-19 caused by large-scale sports competitions. However, quantitative analysis on the appropriate frequency of NAT is scarce, and the cost-effectiveness and necessity of high-frequency NAT remain to be fully explored and validated. This study aims to optimize the COVID-19 surveillance strategies through cost-effectiveness analysis for the Tokyo 2020 Olympic Games and the upcoming Beijing 2022 Olympic Winter Games. METHODS: A total of 18 scenarios were designed regarding the NAT frequency, symptom monitoring, and strengthening close-contact control. An agent-based stochastic dynamic model was used to compare the cost-effectiveness of different NAT scenarios and optimize the surveillance strategies. The dynamics of the proposed model included the arrival and departure of agents, transmission of the disease according to Poisson processes, and quarantine of agents based on regular NATs and symptom onset. Accumulative infections, cost, and incremental cost-effectiveness ratio (ICER) were simulated in the frame of the model. ICER was used to compare the cost-effectiveness of different scenarios. Univariate sensitivity analysis was performed to test the robustness of the results. RESULTS: In Scenario 16, where the competition-related personnel (CRP) received NAT daily and national sports delegation (NSD) with quarantined infections accepted an additional NAT daily, accumulative infection was 320.90 (90 initial infections), the total cost was (United States Dollar) USD 8 920 000, and the cost of detecting out each infection was USD 27 800. Scenario 16 would reduce the total cost by USD 22 570 000 (avoid 569.61 infections), USD 1 420 000 (avoid 47.2 infections) compared with Scenario 10 (weekly NAT, strengthened close contact control) and Scenario 7 (daily NAT, no strengthened close contact control), respectively. Sensitivity analysis showed that the result was most sensitive to the change in basic reproductive number. CONCLUSIONS: High-frequency NATs such as bidaily, daily, and twice a day were cost-effective. NAT daily for CRP with strengthening close-contact control could be prioritized in defense against COVID-19 at large-scale sports competitions. This study could assist policymakers by assessing the cost-effectiveness of NAT scenarios and provide the host country with an optimal COVID-19 surveillance strategy.


Subject(s)
COVID-19 , Beijing , COVID-19/prevention & control , Cost-Benefit Analysis , Humans
3.
China CDC Wkly ; 4(5): 79-82, 2022 Feb 04.
Article in English | MEDLINE | ID: covidwho-1649573

ABSTRACT

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Reducing population mobility and increasing the vaccination rate for severe acute respiratory syndrome coronavirus 2 can decrease the transmission of coronavirus disease 2019 (COVID-19). WHAT IS ADDED BY THIS REPORT?: In order to reduce the incidence of COVID-19 to the levels of influenza after restoring normal mobility, the efficacy against infection needs to be increased to 40% and the efficacy against symptomatic disease needs to be increased to 90%. The efficacy against infection has a more important impact compared to efficacy against symptomatic disease or death on the transmission of COVID-19 at the population level. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: The population should continue maintaining non-pharmaceutical interventions and minimize international movement to prevent transmission of COVID-19. Furthermore, developing new vaccines or promoting booster vaccinations should be considered to increase efficacy.

4.
Front Public Health ; 9: 737817, 2021.
Article in English | MEDLINE | ID: covidwho-1608735

ABSTRACT

Background: Prevention and control of HIV/AIDS and other sexually transmitted diseases (STDs) are major public health priorities in China, but are influenced by the COVID-19 epidemic. In this study, we aimed to quantitatively explore the impact of the COVID-19 epidemic and its control measures on five major STD epidemics in China. Methods: A monthly number of newly reported cases of HIV/AIDS, hepatitis B and C, gonorrhea, and syphilis from January 2010 to December 2020 were extracted to establish autoregressive integrated moving average (ARIMA) models. Each month's absolute percentage error (APE) between the actual value and model-predicted value of each STD in 2020 was calculated to evaluate the influence of the COVID-19 epidemic on the STDs. Pearson correlation analysis was conducted to explore the confirmed COVID-19 case numbers and the COVID-19 control measures' correlations with the case numbers and the APEs of five STDs in 2020. Results: The actual number of five STDs in China was more than 50% lower than the predicted number in the early days of the COVID-19 epidemic, especially in February. Among them, the actual number of cases of hepatitis C, gonorrhea, and syphilis in February 2020 was more than 100% lower than the predicted number (APE was -102.3, -109.0, and -100.4%, respectively). After the sharply declines of STDs' reported cases in early 2020, the case numbers recovered quickly after March. The epidemic of STDs was negatively associated with the COVID-19 epidemic and its control measures, especially for restrictions on gathering size, close public transport, and stay-at-home requirements (p < 0.05). Conclusion: COVID-19 had a significant but temporary influence on the STD epidemic in China. The effective control of COVID-19 is vital for STD prevention. STD services need to be improved to prevent STDs from becoming a secluded corner in the shadow of COVID-19.


Subject(s)
COVID-19 , Epidemics , Sexually Transmitted Diseases , China/epidemiology , Humans , SARS-CoV-2 , Sexually Transmitted Diseases/epidemiology
5.
Bioorg Med Chem ; 53: 116523, 2022 01 01.
Article in English | MEDLINE | ID: covidwho-1525708

ABSTRACT

Since the end of 2019, the outbreak of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has evolved into a global pandemic. There is an urgent need for effective and low-toxic antiviral drugs to remedy Remdesivir's limitation. Hydroxychloroquine, a broad spectrum anti-viral drug, showed inhibitory activity against SARS-CoV-2 in some studies. Thus, we adopted a drug repurposing strategy, and further investigated hydroxychloroquine. We obtained different configurations of hydroxychloroquine side chains by using chiral resolution technique, and successfully furnished R-/S-hydroxychloroquine sulfate through chemical synthesis. The R configuration of hydroxychloroquine was found to exhibit higher antiviral activity (EC50 = 3.05 µM) and lower toxicity in vivo. Therefore, R-HCQ is a promising lead compound against SARS-CoV-2. Our research provides new strategy for the subsequent research on small molecule inhibitors against SARS-CoV-2.


Subject(s)
Antiviral Agents/pharmacology , Hydroxychloroquine/pharmacology , SARS-CoV-2/drug effects , Animals , Antiviral Agents/chemical synthesis , Antiviral Agents/toxicity , Chlorocebus aethiops , Drug Repositioning , Female , Hydroxychloroquine/chemical synthesis , Hydroxychloroquine/toxicity , Male , Mice , Microbial Sensitivity Tests , Stereoisomerism , Vero Cells
6.
Environ Sci Pollut Res Int ; 29(10): 14333-14347, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1449988

ABSTRACT

Environmental factors could influence the epidemic of virus in human; however, the association remains intricate, and the evidence is still not clear in human coronaviruses (HCoVs). We aimed to explore and compare the associations between HCoVs' epidemic and environmental factors globally. Four common HCoVs' data were collected by a systematic literature review, and data of MERS, SARS, and COVID-19 were collected from the World Health Organization's reports. Monthly positive rates of common HCoVs and incidence rates of MERS, SARS, and COVID-19 were calculated. Geographical coordinates were used to link virus data and environmental data. Generalized additive models (GAMs) were used to quantitatively estimate the association of environmental factors with HCoVs' epidemic. We found that there are wide associations between HCoVs and environmental factors on a global scale, and some of the associations were nonlinear. In addition, COVID-19 has the most similarities in associations' direction with common HCoVs, especially for HCoV-HKU1 in four environmental factors including the significantly negative associations with average temperature, precipitation, vegetation coverage (p<0.05), and the U-shaped association with temperature range. This study strengthened the relevant research evidences and provided significant insights into the epidemic rules of HCoVs in general. The similarities between COVID-19 and common HCoVs indicated that it is critically important to strengthen surveillance on common HCoVs and pay more attention to environmental factors' role in surveillance and early warning of HCoVs' epidemic.


Subject(s)
COVID-19 , Coronavirus Infections , Severe Acute Respiratory Syndrome , COVID-19/epidemiology , Coronavirus Infections/epidemiology , Global Health , Humans , Middle East Respiratory Syndrome Coronavirus , SARS Virus , SARS-CoV-2 , Severe Acute Respiratory Syndrome/epidemiology
7.
Front Immunol ; 12: 715464, 2021.
Article in English | MEDLINE | ID: covidwho-1430698

ABSTRACT

The mutants resulted from the ongoing SARS-CoV-2 epidemic have showed resistance to antibody neutralization and vaccine-induced immune response. The present study isolated and identified two novel SARS-CoV-2 neutralizing antibodies (nAbs) from convalescent COVID-19 patients. These two nAbs (XG81 and XG83) were then systemically compared with nine nAbs that were reconstructed by using published data, and revealed that, even though these two nAbs shared targeting epitopes on spike protein, they were different from any of the nine nAbs. Compared with XG81, XG83 exhibited a higher RBD binding affinity and neutralization potency against wild-typed pseudovirus, variant pseudoviruses with mutated spike proteins, such as D614G, E484Q, and A475V, as well as the authentic SARS-CoV-2 virus. To explore potential broadly neutralizing antibodies, heavy and light chains from all 18 nAbs (16 published nAbs, XG81 and XG83) were cross-recombined, and some of the functional antibodies were screened and studied for RBD binding affinity, and neutralizing activity against pseudovirus and the authentic SARS-CoV-2 virus. The results demonstrated that several recombined antibodies had a more potent neutralization activity against variant pseudoviruses compared with the originally paired Abs. Taken together, the novel neutralizing antibodies identified in this study are a likely valuable addition to candidate antibody drugs for the development of clinical therapeutic agents against SARS-CoV-2 to minimize mutational escape.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Broadly Neutralizing Antibodies/immunology , Broadly Neutralizing Antibodies/therapeutic use , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/therapeutic use , Antibodies, Viral/genetics , Antibodies, Viral/therapeutic use , Antibody Affinity/immunology , B-Lymphocytes/immunology , Broadly Neutralizing Antibodies/genetics , COVID-19/immunology , COVID-19/therapy , Cell Line , Epitopes/immunology , Humans , Immunotherapy/methods , Neutralization Tests , SARS-CoV-2/drug effects
8.
Front Immunol ; 12: 693775, 2021.
Article in English | MEDLINE | ID: covidwho-1394758

ABSTRACT

Small number of SARS-CoV-2 epidemic lineages did not efficiently exhibit a neutralization profile, while single amino acid mutation in the spike protein has not been confirmed in altering viral antigenicity resulting in immune escape. To identify crucial mutations in spike protein that escape humoral immune response, we evaluated the cross-neutralization of convalescent plasmas and RBD-specific monoclonal antibodies (mAbs) against various spike protein-based pseudoviruses. Three of 24 SARS-CoV-2 pseudoviruses containing different mutations in spike protein, including D614G, A475V, and E484Q, consistently showed an altered sensitivity to neutralization by convalescent plasmas. A475V and E484Q mutants are highly resistant to neutralization by mAb B38 and 2-4, suggesting that some crucial mutations in spike protein might evolve SARS-CoV-2 variants capable of escaping humoral immune response.


Subject(s)
Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/blood , Antibodies, Viral/immunology , Mutation , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Amino Acid Substitution/genetics , Amino Acid Substitution/immunology , Antibodies, Neutralizing/immunology , Convalescence , Humans , Immune Evasion , Immunity, Humoral , Neutralization Tests , Protein Binding
9.
Front Cell Infect Microbiol ; 11: 663884, 2021.
Article in English | MEDLINE | ID: covidwho-1317217

ABSTRACT

Background: The pandemic of Coronavirus Disease 2019 (COVID-19) brings new challenges for pediatricians, especially in the differentiation with non-COVID-19 pneumonia in the peak season of pneumonia. We aimed to compare the clinical characteristics of pediatric patients with COVID-19 and other respiratory pathogens infected pneumonias. Methods: We conducted a multi-center, cross-sectional study of pediatric inpatients in China. Based on pathogenic test results, pediatric patients were divided into three groups, including COVID-19 pneumonia group, Non-COVID-19 viral (NCV) pneumonia group and Non-viral (NV) pneumonia group. Their clinical characteristics were compared by Kruskal-Wallis H test or chi-square test. Results: A total of 636 pediatric pneumonia inpatients, among which 87 in COVID-19 group, 194 in NCV group, and 355 in NV group, were included in analysis. Compared with NCV and NV patients, COVID-19 patients were older (median age 6.33, IQR 2.00-12.00 years), and relatively fewer COVID-19 patients presented fever (63.2%), cough (60.9%), shortness of breath (1.1%), and abnormal pulmonary auscultation (18.4%). The results were verified by the comparison of COVID-19, respiratory syncytial virus (RSV) and influenza A (IFA) pneumonia patients. Approximately 42.5%, 44.8%, and 12.6% of the COVID-19 patients presented simply ground-glass opacity (GGO), simply consolidation, and the both changes on computed tomography (CT) scans, respectively; the proportions were similar as those in NCV and NV group (p>0.05). Only 47.1% of COVID-19 patients had both lungs pneumonia, which was significantly lower than that proportion of nearly 80% in the other two groups. COVID-19 patients presented lower proportions of increased white blood cell count (16.5%) and abnormal procalcitonin (PCT) (10.7%), and a higher proportion of decreased lymphocyte count (44.0%) compared with the other two groups. Conclusion: Majority clinical characteristics of pediatric COVID-19 pneumonia patients were milder than non-COVID-19 patients. However, lymphocytopenia remained a prominent feature of COVID-19 pediatric pneumonia.


Subject(s)
COVID-19 , Pneumonia , Child , China/epidemiology , Cross-Sectional Studies , Humans , Lung/diagnostic imaging , Pneumonia/epidemiology , Retrospective Studies , SARS-CoV-2
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