The impacts of pandemic on urban housing prices: evidence from the outbreak of COVID-19 in Beijing, 2020

Purpose: The COVID-19 pandemic has significantly raised economic risk and uncertainty worldwide. How does COVID-19 affect urban housing markets? Is there any difference when different areas encounter COVID-19? This study aims to investigate the impacts of the pandemic on housing prices by using Beijing's housing markets data in 2020. Design/methodology/approach: The authors use transaction-level data from April to September in 2020 to conduct a hedonic price analysis of the housing markets in Beijing. The data included 70,843 transactions scraped from a real estate agent's website. The authors use the difference-in-differences approach to evaluate the impacts of the COVID-19 outbreak from the Beijing Xinfadi market (the largest and most important food wholesale market in Beijing) in 2020. Findings: This outbreak of COVID-19 caused a 6.3% drop in housing prices in Beijing from April to September in 2020. However, the impacts of COVID-19 on housing prices in different urban neighbourhoods were spatially heterogeneous. Housing prices in neighbourhoods with industries that rely on face-to-face communication were more affected by the pandemic, while those that can work remotely were less affected. Originality/value: By investigating the impacts of COVID-19 on housing prices in Beijing, this study illustrates that urban housing prices would be impacted by the pandemic, at least in the short term. While the rise and fall of housing prices were found spatially heterogeneous in Beijing, it suggests that urban neighbourhoods with specific socioeconomic characteristics and geographic locations would unfold different resilience when encountering pandemic. By using data scraping and rigorous statistical tools, the study is probably one of the first ones examining the consequences of COVID-19 in intra-urban housing markets. © 2023, Emerald Publishing Limited.

COVID-19 Risk and Control

Coronavirus disease 2019 (COVID-19) is a respiratory infection caused by the virus SARS-CoV-2. Coronaviruses (CoVs), enveloped positive-sense RNA viruses, are further subdivided into four different genera, historically based on serological analysis and now on genetic studies: alpha-, beta-, gamma-, and delta-CoV. The first two mainly infect mammals, while the second two mainly infect birds. There are currently seven known CoVs that can infect humans: HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, SARS-CoV, MERS-CoV, and SARS-Cov-2. The last three are beta-CoVs, which are relatively high in infectivity and disease severity and pose a great threat to public health security in all countries. Current studies have shown that SARS-Cov-2 has already mutated into two lineages called "L-type" and "S-type." The phylogenetic tree indicates that the S-type is older than the L-type and more closely resembles bat coronaviruses. However, the L-type accounts for a larger proportion in the samples currently collected, suggesting that the recently evolved L-type spreads or replicates faster in human populations [1]. © People's Medical Publishing House, PR of China 2021, corrected publication 2021.

Intelligent optimization design of electron barrier layer for AlGaN-based deep-ultraviolet light-emitting diodes

AlGaN-based deep-ultraviolet light-emitting diodes (DUV LEDs) are widely used in sterilization, sensing, water purification, medical treatment, non-line of sight (NLOS) communication and many other fields. Especially it has been reported that the global novel coronavirus (COVID-19) can be effectively inactivated by the DUV light with a wavelength below 280 nm (UVC) within a few seconds, which has also attracted great attention. However, the external quantum efficiency (EQE) of UVC LED is still at a low level, generally not more than 10%. As an important component of EQE, internal quantum efficiency (IQE) plays a crucial role in realizing high-performance DUV-LED. In order to improve the IQE of AlGaN-based DUV-LED, this work adopts an electron blocking layer (EBL) structure based on InAlGaN/AlGaN superlattice. The results show that the superlattice EBL structure can effectively improve the IQE compared with the traditional single-layer and double-layer EBL structure for the DUV-LED. On this basis, the optimization method based on JAYA intelligent algorithm for LED structure design is proposed in this work. Using the proposed design method, the InAlGaN/AlGaN superlattice EBL structure is further optimized to maximize the LED' s IQE. It is demonstrated that the optimized superlattice EBL structure is beneficial to not only the suppression of electron leakage but also the improvement of hole injection, leading to the increase of carrier recombination in the active region. As a result, the IQE of the DUV-LED at 200 mA injection current is 41.2% higher than that of the single-layer EBL structure. In addition, the optimized structure reduces IQE at high current from 25% to 4%. The optimization method based on intelligent algorithm can break through the limitation of the current LED structure design and provide a new method to improve the efficiency of AlGaN-based DUV-LED. © 2023 Chinese Physical Society.

Effectiveness of project￣based on learning of COVID￣19 prevention and protection among primary school students

Objective To evaluate the effectiveness of project- based learning of COVID- 19 prevention and protection among pri- mary school students. Methods In February 2020 all the participants were selected from grade one grade three and grade six in a primary school in Hefei and were randomly assigned into the experimental group 532 students and the control group 530 students. Project- based learning methods was administered in health education of COVID- 19 prevention and protection in the ex- perimental group for two weeks with the traditional health education for the control group. Questionnaire survey was conducted be- fore and after experimental. Results After carrying out project- based learning the awareness rate of COVID- 19 protection knowl- edge in the project group was 99.43% while that in the control group was 74.74% after traditional education methods the propor- tion of excellent students was 96.43% in intervention group and 45.11% in control group with significant statistical difference χ2 = 346.62 P<0.01. Conclusion Project- based learning is superior than traditional health education in terms of improvement in self- protection against COVID- 19 among students. © 2022 The authors.

Experts' consensus on severe acute respiratory syndrome coronavirus-2 vaccination of children.

At present, severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is still rampant worldwide.As of September 10, 2021, there were about 222 million confirmed cases of corona virus disease 2019(COVID-19)and more than 4.6 million deaths worldwide.With the development of COVID-19 vaccines and the gradual vaccination worldwide, the increasing number of cases in children and unvaccinated young people has drawn attention.According to World Health Organization surveillance data, the proportion of COVID-19 infection cases in children gradually increased, and the proportion of cases in the age groups of under 5 years and 5-14 years increased from 1.0% and 2.5% in January 2020 to 2.0% and 8.7% in July 2021, respectively.At present, billions of adults have been vaccinated with various COVID-19 vaccines worldwide, and their protective effects including reducing infection and transmission, reducing severe disease and hospitalization, and reducing death, as well as high safety have been confirmed.Canada, the United States, Europe and other countries have approved the emergency COVID-19 vaccination in children and adolescents aged 12 to 17 years, and China has also approved the phased vaccination of COVID-19 vaccination in children and adolescents aged 3 to 17 years. For smooth advancement and implementation of COVID-19 vaccination in children, academic institutions, including National Clinical Research Center for Respiratory Diseases, National Center for Children's Health, and The Society of Pediatrics, Chinese Medical Association organized relevant experts to reach this consensus on COVID-19 vaccination in children.Copyright © 2021 by the Chinese Medical Association.

Online and Offline Mixed Teaching Reform in the Practical Course of Artificial Intelligence and Application

It is necessary to ensure the quality of students' courses, especially practical courses, which is an important part of higher education, and plays a positive role in promoting and popularizing the improvement of innovation and entrepreneurship in the face of the non suspension of classes and schools under the COVID-19. This paper explores the mode of online and offline combined with ideological and political education mixed teaching reform in the course, in order to explore the educational functions and ideological and political elements of the course from the practical contents and objectives from the practical course of artificial intelligence foundation, explore the implementation methods and teaching concepts of ideological and political education in the course, so that students can better master and understand knowledge comprehensively, improve the results of students' ideological and moral education, and explore the reform mode which satisfy the requirements of talent training. © 2022 IEEE.

Research on Anti-epidemic Material Delivery Robot

After the occurrence of the COVID-19, preventing cross infection has become a top priority. Therefore, it is proposed to use robots to replace people to distribute anti epidemic materials, so as to reduce human contact. By planning the trajectory of the robot in advance, and using mechanical arms and claws to achieve accurate grasp and delivery of anti epidemic materials, it can carry out material distribution in the isolated inpatient department, and can independently locate and deliver products, goods, etc. in a complex environment. It has strong cargo carrying capacity, and has the dual functions of traditional delivery robots and indoor delivery services. Its use can greatly reduce the infection rate in the epidemic and deliver materials in time. © 2022 IEEE.

Twenty key issues on severe acute respiratory syndrome coronavirus-2 vaccination in children.

Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is still worldwide.As a vulnerable group, severe and dead pediatric cases are also reported.Under this severe epidemic situation, children should be well protected.With the widespread vaccination of SARS-CoV-2 vaccine in adults, the infection rate have decreased.Therefore, SARS-CoV-2 vaccine inoculation for children groups step by step is of great significance to the protection of children and the prevention and control of corona virus disease 2019(COVID-19) as a whole.But the safety of children vaccinated with SARS-CoV-2 vaccine is a main concern of parents.Therefore, in order to ensure the safety of vaccination and the implementation of vaccination work, National Clinical Research Center for Respiratory Diseases, National Center for Children's Health and the Society of Pediatrics, Chinese Medical Association organized experts to interpret the main issue of parents about SARS-CoV-2 vaccine for children, in order to answer the doubts of parents.Copyright © 2021 by the Chinese Medical Association.

Screening and Identification of Host Proteins Interacting with PDCoV S1-CTD

The C-terminal domain (CTD) of porcine deltacoronavirus S1 subunit is the main region which induces the neutralizing antibody. S1-CTD was expressed by HEK-293T eukaryotic expression system and purified, and porcine ileal epithelium cells membrane proteins were extracted to investigate porcine host proteins that interact with it. Thirty-two suspected interacting host proteins were obtained by co-inmunprecipitation (Co-IP) and mass spectrometry. Eukaryotic expression plasmid of KIF1 binding protein (KIFBP) was constructed, and the interaction between KIFBP and S1-CTD was identified by Co-IP and laser confocal microscopy. All results proved that KIFBP interacted with S1-CTD and co-located in cytoplasm. Further research indicated that overexpression of KIFBP could effectively reduce the viral mRNA level and the viral titer in which the mRNA level decreased by about 70%, and the viral titer decreased by 101.6TCID50. In conclusion, a host protein KIFBP interacting with PDCoV S1-CTD was screened and identified in this study which provides a theoretical basis for understanding the pathogenesis of PDCoV.

Generation of APN-chimeric gene-edited pigs by CRISPR/Cas9-mediated knock-in strategy

The prevalence of porcine enteric coronaviruses (PECs), including transmissible gastroenteritis virus (TGEV), swine acute diarrhea syndrome coronavirus (SADS-CoV), porcine delta coronavirus (PDCoV), and porcine epidemic diarrhea virus (PEDV), poses a serious threat to animal and public health. Here, we aimed to further optimize the porcine aminopeptidase N (pAPN) gene editing strategy to explore the balance between individual antiviral properties and the biological functions of pAPN in pigs. Finally, APN-chimeric gene-edited pigs were produced through a CRISPR/Cas9-mediated knock-in strategy. Further reproductive tests indicated that these gene-edited pigs exhibited normal pregnancy rates and viability. Notably, in vitro viral challenge assays further demonstrated that porcine kidney epithelial cells isolated from F1-generation gene-edited pigs could effectively inhibit TGEV infection. This study is the first to report the generation of APN-chimeric pigs, which may provide a natural host animal for characterizing PEC infection with APN and help in the development of better antiviral solutions. © 2022 Elsevier B.V.

Digital Twin for Transportation Big Data: A Reinforcement Learning-Based Network Traffic Prediction Approach

Vehicular Ad-Hoc Networks (VANETs), as the crucial support of Intelligent Transportation Systems (ITS), have received great attention in recent years. With the rapid development of VANETs, various services have generated a great deal of data that can be used for transportation planning and safe driving. Especially, with the advent of Coronavirus Disease 2019 (COVID-19), the transportation system has been impacted, thus novel modes of transportation planning and intelligent applications are necessary. Digital twins can provide powerful support for artificial intelligence applications in Transportation Big Data (TBD). The features of VANETs are varying, which arises the main challenge of digital twins applying in TBD. Network traffic prediction, as part of digital twins, is useful for network management and security in VANETs, such as network planning and anomaly detection. This paper proposes a network traffic prediction algorithm aiming at time-varying traffic flows with a large number of fluctuations. This algorithm combines Deep Q-Learning (DQN) and Generative Adversarial Networks (GAN) for network traffic feature extraction. DQN is leveraged to carry out network traffic prediction, in which GAN is involved to represent Q-network. Meanwhile, the generative network can increase the number of samples to improve the prediction error. We evaluate the performance of our method by implementing it on three real network traffic data sets. Finally, we compare the two state-of-the-art competing methods with our method. IEEE

Symptoms associated with nucleic acid turning-negative-time in COVID-19 patients?

To explore on the association between nucleic acid turning-negative-time and traditional Chinese medicine (TCM) symptoms in coronavirus disease 2019 (COVID-19) patients with the Omicron variant.Method:: For this retrospective cross-sectional study, we enrolled 189 patients with COVID-19 (age 20–90 years) were included. multiple linear regression models were used to investigate the TCM symptoms affecting the nucleic acid turning-negative-time of COVID-19 patients, during the process of data analysis, taking with nucleic acid turning-negative-time as the dependent variable, and TCM symptoms as independent variables, and at the same time, sex, age, hypertension, diabetes, and coronary heart disease were as confounding variables. Results:: The study found that the most common TCM symptoms of COVID-19 patients with Omicron were cough, dry throat, expectoration, fever, sore throat, pharyngeal itching, running nose, and nasal congestion. Regression analysis showed that the fit regressive equation showed a significant difference (F = 4.286, P < 0.001), R = 0.400, the adjusted R 2 = 0.123, and three variables in the regression equation showed significant difference (P < 0. 05). The results showed that nucleic acid turning-negative-time was mostly related to constipation, fever, and expectoration. If the patients had the symptoms of constipation, fever, and expectoration;that is, if patients showed these symptoms, the turning-negative-time of nucleic acid in patients with Omicron will be prolonged. Conclusions:: Treatment based on symptoms for patients with constipation, fever, and expectoration may have important clinical significance for the COVID-19 patients with Omicron.

[Research on the interaction between COVID-19 and influenza].

Since the global pandemic of COVID-19, different countries have implemented various prevention and control measures, which has affected the epidemic characteristics of respiratory infectious diseases such as influenza. From 2020 to 2021, the level of influenza activity was relatively low, but it is necessary to be alert that with the adjustment of national prevention and control measures, influenza may have a relatively strong epidemic rebound. In order to deal with influenza epidemic, experts were organized to publish a series of influenza studies in this issue, suggesting that influenza prevention and control cannot be underestimated during the COVID-19 pandemic. It is suggested to carry out research on the interaction between COVID-19 and influenza to explore the epidemic characteristics of the disease, develop new technologies and tools to improve the efficiency of monitoring and early warning, identify obstacles to vaccination, promote the scientific implementation of intervention measures, and achieve joint prevention and control of multiple diseases.

[Thoughts and suggestions on co-administration of seasonal influenza vaccine and COVID-19 vaccine].

In the context of the global pandemic of COVID-19, the epidemic intensity, epidemic characteristics and infection risk of influenza have presented new features. COVID-19 and influenza have simultaneously emerged in many regions of the world. COVID-19 and influenza are similar in terms of transmission mode, clinical symptoms and other aspects. There are also similarities in the mechanism of influenza virus and novel coronavirus on cells. At the same time, it is feasible and significant to do a good job in the prevention and control of COVID-19 and influenza. This paper discusses the relevant strategies and measures for the joint prevention and control of influenza and novel coronavirus from the aspects of influenza vaccination to prevent co-infection, simultaneous vaccination of influenza vaccine and novel coronavirus vaccine, etc., and puts forward corresponding thoughts and suggestions, in order to provide scientific support for the formulation of strategies on seasonal influenza vaccine and novel coronavirus vaccination.

Post-hospitalisation respiratory and physical functions in patients with SARS-CoV-2 delta.

BACKGROUND Despite growing concern regarding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) delta variant of concern (VOC), the respiratory and physical functions of patients with delta VOC post-discharge have not been investigated compared to those of patients with ancestral SARS-CoV-2.METHODS Sixty-three discharged patients with coronavirus disease (COVID-19) were included. Patients were divided into delta VOC and ancestral SARS-CoV-2 groups. On Day 14 post-discharge, differences in chest computed tomography, modified Medical Research Council and Borg Dyspnoea Scale scores, and Manual Muscle Test scores were compared. Prognoses of respiratory and physical function were compared between patients who recovered from moderate and severe COVID-19.RESULTS Of the 63 patients, respectively 28 and 35 were in the delta VOC and ancestral SARS-CoV-2 groups. On Day 14 post-discharge, 35 patients (56.5%) had abnormalities on imaging. Visual semi-quantitative scores of both lungs were significantly higher in the severe group. However, there was no difference in this or any other score ratings between the groups.CONCLUSION At 14 days post-discharge, ground glass opacities and pleural thickening were the most common residual findings; no difference in respiratory and physical functions during the convalescence period were noted in patients with SARS-CoV-2 delta VOC and ancestral SARS-CoV-2.

Response Adapted Ultra Low Dose Radiation Therapy for the Definitive Management of Orbital Indolent B-Cell Lymphoma

Radiation therapy (RT) to doses of 24-30 Gy is used for the treatment of indolent B-cell lymphoma (BCL);however, significant acute and late ocular effects are common. We aimed to develop a response adapted (RA) strategy that maintains excellent disease outcomes but reduces orbital morbidity. We performed a phase II prospective study of a RA strategy in 50 patients (pts) with stage I-IV orbital indolent BCL. Pts were treated with ultra-low dose (ULD) RT to 4 Gy in 2 fractions and assessed in 3-month intervals for response. Pts with persistent orbital lymphoma were offered an additional 20 Gy in 10 fractions. Pts that had a complete response (CR) to ULD RT were observed. We also evaluated this treatment strategy in a separate 55 pt retrospective cohort. From July 2015-January 2021 51 pts were enrolled. Fifty evaluable pts had follow-up for study inclusion. The median age was 63 years (29-88);62% were female (n=31). Pts had MALT lymphoma (n=32, 64%), follicular lymphoma (FL, n=16, 32%) and low grade BCL (n=6, 12%). Most pts (62%, n=31) had stage I disease limited to one (n=28) or both (n=3) orbits. Pts had newly diagnosed (n=36, 72%);relapsed (n=9, 18%) and refractory lymphoma (n=5, 10%). At a median follow up of 35 months [95% CI 22.2 – 37.4], 90% of pts (n=45) experienced a CR to RA RT, including 44 pts that had a CR to ULD RT (median time to CR 3.4 months) and 1 pt that had a CR after an additional 20 Gy. No local recurrences were observed. Treatment was well tolerated with no grade ≥3 toxicity. Five pts did not have a CR to planned RA therapy including 1 pt that refused additional RT, one pt treated with rituximab, one pt that had a PR on initial evaluation but has not returned for subsequent in person evaluations due to COVID, one pt being observed with stable disease and a final pt that received an additional 20 Gy to the orbit that has a persistent stable mass after the 20 Gy. In a planned subset analysis of 26 pts with newly diagnosed stage 1 disease (MALT, n=22;FL, n=3;low grade BCL, n=1);92.3% (n=24) had a CR to RA RT, with one pt requiring an additional 20 Gy. For all 26 pts with newly diagnosed stage 1 disease, the 3-year freedom from distant relapse rate was 90.4% with 3 distant relapses (contralateral orbit, n=2;paratracheal nodes, n=1). The median follow-up among the 55 pts (MALT, n=38;FL, n=13;low grade B-cell lymphoma, n=4) treated in the retrospective cohort between March 2013 and October 2021 was 28.7 months (95% CI 21.2 - 36.1);98% (n=54) of pts had a CR with RA RT, including 2 pts with a CR after an additional 20 Gy. The remaining pt went on to receive systemic therapy in lieu of additional RT for persistent disease. Among the 54 pts that had a CR with RA RT there was one local relapse in a pt with conjunctival FL 27.8 months after experiencing a CR to ULD RT. This pt received 20 Gy with resolution of the locally relapsed disease. We observed excellent disease control with negligible toxicity in the first prospective study assessing this novel approach of RA ULD RT for pts with indolent B-cell lymphoma. [ FROM AUTHOR] Copyright of International Journal of Radiation Oncology, Biology, Physics is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

A phase 2 clinical trial of axitinib and avelumab in patients with recurrent/metastatic adenoid cystic carcinoma (ACC)

Background: ACC is a heterogeneous neoplasm and there is no standard treatment for patients (pts) with recurrent/metastatic (R/M) disease. Vascular endothelial growth factor receptor inhibitors (VEGFRi) are frequently used to treat R/M ACC rendering mostly disease stabilization. ACC is resistant to PD-1/PD-L1 inhibitors (PD-L1i), consistent with its low mutational burden and uninflamed immune microenvironment. We hypothesized that the immunomodulatory role of VEGFRi (axitinib) would enhance PD-L1i (Avelumab) activity and be a more effective therapy for R/M ACC. Methods: Eligible pts had R/M ACC with radiological or clinical progression within 6 months (mos) of enrollment. Treatment consisted of axitinib 5 mg PO bid and avelumab 10 mg/Kg IV every 2 weeks. Primary endpoint was objective response rate (ORR) per RECIST 1.1;secondary endpoints included duration of response (DOR), progression-free survival (PFS), overall survival (OS), and toxicity. Simon 2-stage design was applied to test the null hypothesis of ORR ≤ 5% versus the alternative ORR ≥ 20%;≥ 4 responses out of 29 pts was required to reject the null hypothesis. Results: 41 pts enrolled from 07/24/19 to 06/29/ 21;28 were evaluable for the primary endpoint (7 screen failures, 6 evaluable for safety only due to loss of insurance/logistics issues related to COVID-19 pandemic);16 pts were treated in first-line. Mutation data was available for 23 of 28 evaluable pts;7 had NOTCH1 activating mutations. The ORR was 17.9% (5/28, 95%CI: 6.1-36.9%). One response was unconfirmed (pt progressed in non-target lesions 2 mos after achieving a PR), for a confirmed ORR of 14.3% (95%CI: 4-32.7%). The median follow-up time for the 15 alive pts was 11.6 mos (min-max: 7.7-29.2 mos). Median PFS was 7.2 mos (95%CI: 3.7-11.7 mos) with a 6-mos PFS rate of 57% (95%CI: 41-79%). Median OS was 17.4 mos (95%CI: 13-NA). 5 pts remain on therapy, 2/5 with a PR. The median DOR for the 5 responders was 5.2 mos (95% CI: 3.7-NA mos). The most common treatment-related adverse events (TRAEs) were fatigue (62%), hypertension (32%), diarrhea (29%), and stomatitis (29%). Serious TRAEs occurred in 8 (24%) pts, all grade 3 and manageable. 4 (15%) pts discontinued avelumab and 9 (32%) underwent axitinib dose reduction due to toxicity. Conclusions: The study reached its primary endpoint with ≥ 4 responses out of 28 evaluable pts (ORR of 17.8%;confirmed ORR of 14.3%). The ORR and 6- mos PFS rate of 57% with axitinib and avelumab compares favorably with single agent axitinib and warrants further study of the combination.

[Introduction and implications of WHO position paper: vaccines against influenza, May 2022].

On May 13, 2022, World Health Organization(WHO) Position Paper on Influenza Vaccine (2022 edition) was published. This position paper updates information on influenza epidemiology, high risk population, the impact of immunization on disease, influenza vaccines and effectiveness and safety, and propose WHO's position and recommendation that all countries should consider implementing seasonal influenza vaccine immunization programmes to prepare for an influenza pandemic. In addition, it proposes that the influenza surveillance platform can be integrated with the surveillance of other respiratory viruses, such as SARS-CoV-2 and Respiratory Syncytial Virus. This position paper has some implications for the prevention and control of influenza and other respiratory infectious diseases in China: (1) Optimize influenza vaccine policies to facilitate the implementation of immunization services; (2) Influenza prevention and control should from the perspective of Population Medicine focus on the individual and community to integrate with "Promotion, Prevention, Diagnosis, Control, Treatment, Rehabilitation"; (3) Incorporate prevention and control of other respiratory infectious diseases such as influenza, COVID-19, respiratory syncytial virus and adenovirus, and intelligently monitor by integrating multi-channel data to achieve the goal of co-prevention and control of multiple diseases.

[Strengthen evaluation of vaccine effectiveness to facilitate scientific and targeted prevention and control of the COVID-19 pandemic].

The COVID-19 continues to spread throughout the world, and local clusters and outbreaks related to overseas imports have occurred in many places in China. Vaccination against COVID-19 is one of the most effective tools to prevent disease, severe illness and death. For vaccines developed and used by China, it is particularly important for scientific and targeted prevention and control to study different outbreak scenarios, to conduct in-depth real-world research on SARS-CoV-2 variants, and to further promote vaccine development and technical reserves. This article commented the effectiveness of COVID-19 vaccine, and prospected the future research on vaccine efficacy, immunization strategy and vaccine development, which provided evidence for optimizing vaccination strategy.