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1.
12th International Symposium on Parallel Architectures, Algorithms and Programming (PAAP) ; : 52-55, 2021.
Article in English | English Web of Science | ID: covidwho-1883137

##### ABSTRACT

The outbreak of COVID-19 calls for the improvement of infectious disease dynamics model to meet the requirements of future infectious disease's prediction and risk assessment. On the basis of SEIR model, a new transmission dynamics model named as SSEIR is proposed. In order to describe the dynamics evolution of the SSEIR model, a new set of ordinary differential equations (ODE) is constructed. The SSEIR dynamics model is used to simulate and predict the progress of pandemic situation inWuhan, China. Because that the suspected people have different dynamics characteristics from the susceptible people and the exposed people, this paper put them in a new independent category. To describe the dynamics evolution of SSEIR model, a new set of ordinary differential equations (ODE) is constructed. The SSEIR model can be used to simulate and predict the progress of infectious diseases.

2.
IEEE International Conference on Mechatronics and Automation (IEEE ICMA) ; : 950-955, 2021.
Article in English | English Web of Science | ID: covidwho-1883121

##### ABSTRACT

Due to the COVID-19 epidemic, there has been a high demand for non-contact diagnostic equipment that can reduce exposure and cross-infection. A non-contact medical detection robot is a type of diagnostic equipment and medical service robot with a wide application prospect. However, few non-contact medical detection robots have been designed to collect patients' physiological parameters when they are in inconvenient situations, such as bedridden, during clinical usage. A six-degree-of-freedom (six-DOF) face tracking method based on a six-DOF robot is proposed in this paper. In the proposed system, a face detector equipped with a camera attached to the robot's wrist is used to obtain the real-time face depth and attitude information. The optimal target attitude of the camera is calculated according to the constraints in the base coordinate system. A closed-loop controller is designed to control the robot to reach the target position and posture smoothly. The experiment with a six-DOF robot has verified that the proposed system can achieve the real-time tracking of human faces by a camera. The proposed method can also be used in many other scenarios where six-DOF face tracking is required by robots.

3.
PubMed; 2022.
Preprint in English | PubMed | ID: ppcovidwho-337980

##### ABSTRACT

Network medicine has been pursued for Covid-19 drug repurposing. One such approach adopts structural controllability, a theory for controlling a network (the cell). Motivated to protect the cell from viral infections, we extended this theory to total controllability and introduced a new concept of control hubs. Perturbation to any control hub renders the cell uncontrollable by exogenous stimuli, e.g., viral infections, so control hubs are ideal drug targets. We developed an efficient algorithm for finding all control hubs and applied it to the largest homogenous human protein-protein interaction network. Our new method outperforms several popular gene-selection methods, including that based on structural controllability. The final 65 druggable control hubs are enriched with functions of cell proliferation, regulation of apoptosis, and responses to cellular stress and nutrient levels, revealing critical pathways induced by SARS-CoV-2. These druggable control hubs led to drugs in 4 major categories: antiviral and anti-inflammatory agents, drugs on central nerve systems, and dietary supplements and hormones that boost immunity. Their functions also provided deep insights into the therapeutic mechanisms of the drugs for Covid-19 therapy, making the new approach an explainable drug repurposing method. A remarkable example is Fostamatinib that has been shown to lower mortality, shorten the length of ICU stay, and reduce disease severity of hospitalized Covid-19 patients. The drug targets 10 control hubs, 9 of which are kinases that play key roles in cell differentiation and programmed death. One such kinase is RIPK1 that directly interacts with viral protein nsp12, the RdRp of the virus. The study produced many control hubs that were not targets of existing drugs but were enriched with proteins on membranes and the NF-$\kappa$B pathway, so are excellent candidate targets for new drugs.

4.
13th IEEE Global Engineering Education Conference, EDUCON 2022 ; 2022-March:652-655, 2022.
Article in English | Scopus | ID: covidwho-1874219

##### ABSTRACT

This article proposes a method to remotely control the robot in the laboratory through the Kinect camera to solve the impact of the Covid-19 epidemic on the laboratory teaching experience which allows users to remotely control robots through their own body movements to understand the principles of robots. It is used to solve the problem of fewer students willing to participate in robot remote education. In this study, the Azure Kinect DK camera was used to collect the motion posture of the upper limbs of the human body. The Kinect camera calculates the frames of human arm joints' motion. The control system calculates the direction of motion of each joint of the human body based on the quaternion by mapping the heterogeneous human joints with the robot joints. Make the posture of the human arm swing correspond to the posture of the robot's movement. Thus, the robot in the laboratory can be driven remotely through Azure Kinect DK. By using the method described in this article, students use the camera's motion capture system to remotely manipulate the robot to grab some simple objects. Through the method described in this research, students can carry out some simple operations on the robots in the laboratory from remote. So it is convenient for students to understand the basic principles of robots and achieve the purpose of better remote experimental teaching. At the same time, students can get practical application of motor servo control, ergonomics, physical simulation engine, digital twin system, etc. © 2022 IEEE.

5.
Frontiers in Earth Science ; 10:14, 2022.
Article in English | Web of Science | ID: covidwho-1869357

##### ABSTRACT

The research of atmospheric aerosol in mountain glacier areas has attracted more and more people's attention. For the first time, a field observation study of total suspended particles (TSPs) for four seasons from September 2019 to August 2020 was carried out at the Tianshan Glaciological Station in the source area of Urumqi River, East Tianshan Mountains, China. The TSPs presented typical seasonal characteristics of high in autumn and low in winter, with the annual average value of 181 +/- 170 mu g m(-3). Concentrations of Ca2+, SO42-, NO3-, Cl-, NH4+ and K+, OC, EC were elevated in autumn. The influence of stationary source emissions was stronger than mobile sources, which was explained by the average ratio of NO3-/SO42- (0.31 +/- 0.17). The concentration of secondary organic carbon (SOC) was higher in summer and autumn, especially in summer, indicating that secondary formation processes of organic aerosols were frequent in summer. Impact of fossil fuel combustion sources were evident over the Glaciers, corroborated by the diagnostic mass ratios of OC/EC (0-21.4, 3.38) and K+/EC (0-0.31, 0.08). The factor analysis illustrated that aerosols were mainly affected by rock salt, dust, coal combustion, and automobile exhaust. The local sources made significant contributions to TSPs in the source of Urumqi River by the results of Results of Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model and potential source contribution function (PSCF).

6.
Chinese Journal of Experimental Traditional Medical Formulae ; 28(11):125-131, 2022.
Article in Chinese | Scopus | ID: covidwho-1863361

##### ABSTRACT

7.
Antimicrobial Stewardship and Healthcare Epidemiology ; 2(1), 2022.
Article in English | Scopus | ID: covidwho-1860205

##### ABSTRACT

We performed severe acute respiratory coronavirus virus 2 (SARS-CoV-2) antinucleocapsid IgG testing on 5,557 healthcare providers and found a seroprevalence of 3.9%. African Americans were more likely to test positive than Whites, and HCWs with household exposure and those working on COVID-19 cohorting units were more likely to test positive than their peers. ©

8.
Frontiers in Marine Science ; 9:22, 2022.
Article in English | Web of Science | ID: covidwho-1855364

##### ABSTRACT

Using AIS data to mine the dynamic characteristics of fishery resource exploitation helps to carry out scientific management of fishery and realize the sustainable development of marine resources. We proposed a framework that integrates multiple AIS data processing and analysis modules, which can efficiently divide fishing voyages, determine the fishing activities and identify fishing types, and provide near real-time analysis results on the number of fishing vessels, fishing duration, voyages and so on. The framework was applied to 1.68 billion AIS trajectory data points of approximately 588,000 fishing vessels. We selected China's sea areas overall and six fishing grounds as the research area, explored the characteristics of fishing vessel activities in winter and spring of 2019, and analyzed the impact of COVID-19 on winter-spring fishing in China in 2020. In 2019, our results showed that the number of fishing vessels in China's sea areas gradually increased over time, with the Chinese New Year holiday affecting fishing activities at the corresponding time but having little impact on the entire month. We found that the changing laws of the fishing duration and voyages in the inshore fishing grounds were similar to those of the number of fishing vessels, which increased to varying degrees over time. Gillnetters were the most numerous fishing vessel type operating in the inshore fishing grounds with increased in spring, while seiners had an absolute advantage in the Xisha-Zhongsha fishing ground. In 2020, during the occurrence period of COVID-19, the fishing activities in China's sea areas was almost unaffected. During the outbreak period, the number, distribution range, activity intensity, and fishing duration of fishing vessels all experienced a relatively large decline. After the epidemic was effectively controlled, they were rapidly increased. In addition, we found that compared with the Government Response Stringency Index, the number of fishing vessels and the number of new confirmed cases showed a more obvious negative correlation. By processing, mining and analyzing AIS data with high spatial-temporal granularity, this study can provide data support for the reasonable development of fishery resources, and help fishery practitioners make wise decisions when responding to unexpected emergencies (e.g. pandemics).

9.
Jiaotong Yunshu Xitong Gongcheng Yu Xinxi/Journal of Transportation Systems Engineering and Information Technology ; 22(2):186-196 and 205, 2022.
Article in Chinese | Scopus | ID: covidwho-1847860

##### ABSTRACT

To analyze the impact of COVID-19 on the travel mode choice behavior with diverse shared mobility services, this study designed the stated preference (SP) questionnaire for the multi-modal transportation system which include conventional travel modes, ride hailing, ride sharing, car sharing, and bike sharing. The mixed Logit models with panel data were proposed to investigate the travel mode choices before and during COVID-19. The influence differences of explanatory variables are compared, and the joint effects of perceived pandemic severity and mode choice inertia are examined. Based on the elasticity analysis, the mode choice preferences are predicted corresponding to different management policies under COVID-19 pandemic. The results indicate that the perception to pandemic severity has significant impacts on the ridership of ride sharing and car sharing, and the mode choice inertia obviously affects the usage of ride hailing, car sharing, and bike sharing. When the perceived pandemic severity reduces to 30%~50%, the strategy of increasing parking charge to 1.6~3.0 times would reduce the usage of private car to pre-pandemic condition, and the car sharing with lower close contact risk could become a main substitute. When the perceived pandemic severity is higher than 60%, the strategy of increasing the travel safety of ride sharing to 1.4~3.6 times would improve the ridership. Copyright © 2022 by Science Press.

10.
Hong Kong Journal of Paediatrics ; 27(2):118-125, 2022.
Article in English | Scopus | ID: covidwho-1843202

##### ABSTRACT

11.
Journal of Affective Disorders Reports ; 9, 2022.
Article in English | Scopus | ID: covidwho-1838935

##### ABSTRACT

Introduction: Students worldwide are at marked risk of suicidal ideation/behavior, depression, and low positive mental health (PMH). Medical students are suspected to be a particularly burdened group. On this background, the aim of the present study was to determine prevalence rates of suicidal ideation/behavior, depression and PMH, among Chinese medical students compared to students from other disciplines. Methods: A total of 2,695 Chinese students (41.2% women;age: M = 18.86, SD = .60, range: 18–21), including 461 medical students, filled out self-report measures on suicidal ideation/behavior, depression, and PMH. Results: Twelve-month suicidal ideation was reported by 10.2% of the medical students and by 11.5% of the other students. Medical students had significantly lower levels of depression symptoms and significantly higher levels of PMH than students from other disciplines. Complete mental health – according to the dual-factor model of mental health – was reported by more than 84% of the total sample. Limitations: Data were assessed by a self-report survey that is prone to social desirability. Conclusions: Students in the present study displayed high rates of complete mental health – although the survey was conducted in the midst of the Corona pandemic. No evidence was found that medical students are particularly stressed. © 2022

12.
PubMed; 2021.
Preprint in English | PubMed | ID: ppcovidwho-334688

##### ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the current coronavirus disease 2019 (COVID-19) pandemic. It is known that the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 interacts with the human angiotensin-converting enzyme 2 (ACE2) receptor, initiating the entry of SARS-CoV-2. Since its emergence, a number of SARS-CoV-2 variants have been reported, and the variants that show high infectivity are classified as the variants of concern according to the US CDC. In this study, we performed both all-atom steered molecular dynamics (SMD) simulations and microscale thermophoresis (MST) experiments to characterize the binding interactions between ACE2 and RBD of all current variants of concern (Alpha, Beta, Gamma, and Delta) and two variants of interest (Epsilon and Kappa). We report that the RBD of the Alpha (N501Y) variant requires the highest amount of force initially to be detached from ACE2 due to the N501Y mutation in addition to the role of N90-glycan, followed by Beta/Gamma (K417N/T, E484K, and N501Y) or Delta (L452R and T478K) variant. Among all variants investigated in this work, the RBD of the Epsilon (L452R) variant is relatively easily detached from ACE2. Our results combined SMD simulations and MST experiments indicate what makes each variant more contagious in terms of RBD and ACE2 interactions. This study could help develop new drugs to inhibit SARS-CoV-2 entry effectively. Abstract figure:

13.
PubMed; 2021.
Preprint in English | PubMed | ID: ppcovidwho-334610

##### ABSTRACT

IMPORTANCE: Risk calculators can facilitate shared medical decision-making 1 . Demographics, comorbidities, medication use, geographic region, and other factors may increase the risk for COVID-19-related complications among patients with IBD 2,3 . OBJECTIVES: Develop an individualized prognostic risk prediction tool for predicting the probability of adverse COVID-19 outcomes in patients with IBD. DESIGN SETTING AND PARTICIPANTS: This study developed and validated prognostic penalized logistic regression models 4 using reports to Surveillance Epidemiology of Coronavirus Under Research Exclusion for Inflammatory Bowel Disease (SECURE-IBD) from March-October 2020. Model development was done using a training data set (85% of cases reported March 13 - September 15, 2020), and model validation was conducted using a test data set (the remaining 15% of cases plus all cases reported September 16-October 20, 2020). MAIN OUTCOMES AND MEASURES: COVID-19 related:Hospitalization+: composite outcome of hospitalization, ICU admission, mechanical ventilation, or deathICU+: composite outcome of ICU admission, mechanical ventilation, or deathDeathWe assessed the resulting models' discrimination using the area under the curve (AUC) of the receiver-operator characteristic (ROC) curves and reported the corresponding 95% confidence intervals (CIs). RESULTS: We included 2709 cases from 59 countries (mean age 41.2 years [s.d. 18], 50.2% male). A total of 633 (24%) were hospitalized, 137 (5%) were admitted to the ICU or intubated, and 69 (3%) died. 2009 patients comprised the training set and 700 the test set. The models demonstrated excellent discrimination, with a test set AUC (95% CI) of 0.79 (0.75, 0.83) for Hospitalization+, 0.88 (0.82, 0.95) for ICU+, and 0.94 (0.89, 0.99) for Death. Age, comorbidities, corticosteroid use, and male gender were associated with higher risk of death, while use of biologic therapies was associated with a lower risk. CONCLUSIONS AND RELEVANCE: Prognostic models can effectively predict who is at higher risk for COVID-19-related adverse outcomes in a population of IBD patients. A free online risk calculator ( https://covidibd.org/covid-19-risk-calculator/ ) is available for healthcare providers to facilitate discussion of risks due to COVID-19 with IBD patients. The tool numerically and visually summarizes the patient's probabilities of adverse outcomes and associated CIs. Helping physicians identify their highest-risk patients will be important in the coming months as cases rise in the US and worldwide. This tool can also serve as a model for risk stratification in other chronic diseases. KEY POINTS: Question: How well can a multivariable risk model predict the risk of hospitalization, intensive care unit (ICU) stay, or death due to COVID-19 in patients with inflammatory bowel disease (IBD)?Findings: Multivariable prediction models developed using data from an international voluntary registry of IBD patients and available for use online ( https://covidibd.org/ ) have very good discrimination for predicting hospitalization (Test set AUC 0.79) and excellent discrimination for ICU admission (Test set AUC 0.88) and death (Test set AUC 0.94). The models were developed with a training sample of 2009 cases and validated in an independent test sample of 700 cases comprised of a random sub-sample of cases and all cases entered in the registry during a one-month period after model development. Meaning: This risk prediction model may serve as an effective tool for healthcare providers to facilitate conversations about COVID-19-related risks with IBD patients.

14.
Remote Sensing Letters ; 13(7):651-662, 2022.
Article in English | Web of Science | ID: covidwho-1819662

##### ABSTRACT

The timely and accurate assessment of flooding disasters and economic resilience is significant for post-disaster reconstruction and recovery. In July 2021, the National Polar-orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP-VIIRS) Day/Night Band (DNB) daily data were explored as a proxy to assess the flooding damage caused by heavy rainfall in Zhengzhou City, China. A combination of the night-time light (NTL) changes and the radiation normalization method was used to rapidly identify affected areas and extract populations following the flooding disaster. A daily gross domestic product (GDP) prediction model was developed to evaluate the economic resilience of Zhengzhou City using multi-temporal DNB daily and monthly NTL data. The severity of the disaster was estimated by the extent of power outages, flooding crisis regions, and affected populations. It has been predicted that the Zhengzhou economy is unlikely to be restored to its normal level before the end of 2021 owing to the dual impact of the coronavirus outbreak and flooding disaster;the revised recovery-time prediction is late April 2022. We concluded that our NTL data provided new, simple, and effective insights into the post-flooding assessment of the affected areas, populations, GDP forecast, and economic recovery.

15.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(5): 455-461, 2022 May 09.
Article in Chinese | MEDLINE | ID: covidwho-1818247

##### ABSTRACT

Today, there is greater awareness on the association between oral diseases and respiration diseases after the outbreak of COVID-19. However, confusion regarding the oral health management and medical risk prevention for patients with chronic airway diseases has been remained among dental clinicians. Therefore, the dental experts of the Fifth General Dentistry Special Committee, Chinese Stomatological Association, combined with the experts of respiratory and critical care medicine, undertook the formation of consensus on the oral health management of patients with chronic airway diseases in order to help dental clinicians to evaluate medical risks and make better treatment decision in clinical practice. In the present consensus report, the relationship of oral diseases and chronic airway diseases, the oral health management and the treatment recommendations of patients with chronic airway diseases are provided.

##### Subject(s)
COVID-19 , Oral Medicine , Consensus , Humans , Oral Health
16.
Crohn's and Colitis 360 ; 4(2), 2022.
Article in English | EMBASE | ID: covidwho-1816052

##### ABSTRACT

Background: Patients with inflammatory bowel disease (IBD) may be at risk for development of COVID-19 infection due to innate immune dysfunction and/or immunosuppressive medication use. Methods: In a prospective cohort of adult IBD patients, we captured data on clinical risk factors and IBD medication utilization. The outcome of interest was development of patient-reported laboratory confirmed COVID-19. We calculated incidence rate and performed bivariate analyses to describe the effects of risk factors (age, immunosuppression use, obesity, and race) on development of COVID-19. We utilized logistic regression models to determine the independent risks associated with each factor. Results: A total of 3953 patients with IBD were followed for a mean duration of 212 days (SD 157). A total of 103 individuals developed COVID-19 during follow-up (2.6%, rate of 45 per 1000 person-years). Severity of infection was generally mild. Clinical characteristics were similar among those who developed COVID-19 as compared to not. African American race was associated with incident COVID-19 infection (OR 3.37, 95% CI 1.18-9.59). Immunosuppression use was not associated with development of COVID-19 (OR 1.19, 95% CI 0.72-1.75), nor was age (OR 1.00, 95% CI 0.99-1.02), nor obesity (OR 1.01, 95% CI 0.61-1.66). Conclusions: Immunosuppression use did not increase the risk of development of COVID-19. Therapeutic management of IBD should not be altered to prevent a risk of developing COVID-19.

17.
Evolving Multicultural Education for Global Classrooms ; : 40-67, 2021.
Article in English | Scopus | ID: covidwho-1810541

##### ABSTRACT

During the COVID-19 pandemic, there has been a dramatic surge in anti-Asian racism in the United States. Asians have been blamed for the pandemic. Multicultural education improves cross-cultural understanding and reduces discrimination. Parental racial socialization is an important facet of multicultural education as parents convey racial and ethnic messages to their children. Yet, little research has documented parental racial socialization in Asian families. To address this gap, the authors interviewed 19 Asians and Asian Americans during the COVID-19 pandemic. This chapter shows that discrimination experiences start at an early age and have a lasting impact. Discrimination of Asians is related to the perpetual foreigner stereotype and the model minority myth. These impede how Asians understand their racial discrimination experiences and how families discuss race and ethnicity. All parents in the study expressed how critical parental racial socialization was during the COVID-19 pandemic and suggest that schools are essential to supporting multicultural education at home. © 2021, IGI Global.

18.
Frontiers in Earth Science ; 10, 2022.
Article in English | Scopus | ID: covidwho-1809365

##### ABSTRACT

The Sustainable Development Goals call for taking urgent action to combat climate change and reduce inequalities. However, the related actions have not been effective. Global CO2 emissions in 2021 are projected to rebound to approaching the 2018–2019 peak, and wealth inequality has been increasing at the very top of the distribution resulting from the COVID-19 pandemic. To test whether a trade-off exists between social and environmental benefits, this study calculates county-level wealth inequality with the Gini coefficient and consumption-based household carbon emissions with the emissions coefficient method and input–output modeling. Data are collected from the China Family Panel Studies, the Visible Infrared Imaging Radiometer Suite, the Chinese National Bureau of Statistics and Carbon Emission Account and Datasets in 2014, 2016 and 2018. In addition, a high-dimensional fixed-effects model, an instrumental variable model and causal mediation analysis are adopted to empirically test how wealth inequality influences household carbon emissions and explore the underlying mechanisms. The results show that county-level wealth inequality has a positive impact on household carbon emissions per capita. This means that policies designed to narrow the wealth gap can help reduce carbon emissions, making progress toward multiple SDGs. Moreover, the study reveals that the social norms of the Veblen effect and short-termism play an important role in mediating the relationship between wealth inequality and consumption-based household carbon emissions. This finding provides a new perspective to understand the mechanism behind wealth inequality and household carbon emissions related to climate change. Copyright © 2022 Qin, Wu, Zhang and Wang.

19.
PubMed; 2020.
Preprint in English | PubMed | ID: ppcovidwho-333561

##### ABSTRACT

Increasing age is the strongest predictor of risk of COVID-19 severity. Unregulated cytokine storm together with impaired immunometabolic response leads to highest mortality in elderly infected with SARS-CoV-2. To investigate how aging compromises defense against COVID-19, we developed a model of natural murine beta coronavirus (mCoV) infection with mouse hepatitis virus strain MHV-A59 (mCoV-A59) that recapitulated majority of clinical hallmarks of COVID-19. Aged mCoV-A59-infected mice have increased mortality and higher systemic inflammation in the heart, adipose tissue and hypothalamus, including neutrophilia and loss of gammadelta T cells in lungs. Ketogenic diet increases beta-hydroxybutyrate, expands tissue protective gammadelta T cells, deactivates the inflammasome and decreases pathogenic monocytes in lungs of infected aged mice. These data underscore the value of mCoV-A59 model to test mechanism and establishes harnessing of the ketogenic immunometabolic checkpoint as a potential treatment against COVID-19 in the elderly. HIGHLIGHTS: - Natural MHV-A59 mouse coronavirus infection mimics COVID-19 in elderly.- Aged infected mice have systemic inflammation and inflammasome activation.- Murine beta coronavirus (mCoV) infection results in loss of pulmonary gammadelta T cells.- Ketones protect aged mice from infection by reducing inflammation. ETOC BLURB: Elderly have the greatest risk of death from COVID-19. Here, Ryu et al report an aging mouse model of coronavirus infection that recapitulates clinical hallmarks of COVID-19 seen in elderly. The increased severity of infection in aged animals involved increased inflammasome activation and loss of gammadelta T cells that was corrected by ketogenic diet.

20.
PubMed; 2020.
Preprint in English | PubMed | ID: ppcovidwho-333557

##### ABSTRACT

A spike protein mutation D614G became dominant in SARS-CoV-2 during the COVID-19 pandemic. However, the mutational impact on viral spread and vaccine efficacy remains to be defined. Here we engineer the D614G mutation in the SARS-CoV-2 USA-WA1/2020 strain and characterize its effect on viral replication, pathogenesis, and antibody neutralization. The D614G mutation significantly enhances SARS-CoV-2 replication on human lung epithelial cells and primary human airway tissues, through an improved infectivity of virions with the spike receptor-binding domain in an "up" conformation for binding to ACE2 receptor. Hamsters infected with D614 or G614 variants developed similar levels of weight loss. However, the G614 virus produced higher infectious titers in the nasal washes and trachea, but not lungs, than the D614 virus. The hamster results confirm clinical evidence that the D614G mutation enhances viral loads in the upper respiratory tract of COVID-19 patients and may increases transmission. For antibody neutralization, sera from D614 virus-infected hamsters consistently exhibit higher neutralization titers against G614 virus than those against D614 virus, indicating that (i) the mutation may not reduce the ability of vaccines in clinical trials to protect against COVID-19 and (ii) therapeutic antibodies should be tested against the circulating G614 virus before clinical development. IMPORTANCE: Understanding the evolution of SARS-CoV-2 during the COVID-19 pandemic is essential for disease control and prevention. A spike protein mutation D614G emerged and became dominant soon after the pandemic started. By engineering the D614G mutation into an authentic wild-type SARS-CoV-2 strain, we demonstrate the importance of this mutation to (i) enhanced viral replication on human lung epithelial cells and primary human airway tissues, (ii) improved viral fitness in the upper airway of infected hamsters, and (iii) increased susceptibility to neutralization. Together with clinical findings, our work underscores the importance of this mutation in viral spread, vaccine efficacy, and antibody therapy.