Surveillance and Analysis of SARS-CoV-2 Variant Importation - China, January-June 2022.

Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant is the dominant circulating strain worldwide. To assess the importation of SARS-CoV-2 variants in the mainland of China during the Omicron epidemic, the genomic surveillance data of SARS-CoV-2 from imported coronavirus disease 2019 (COVID-19) cases in the mainland of China during the first half of 2022 were analyzed. Methods: Sequences submitted from January to July 2022, with a collection date before June 30, 2022, were incorporated. The proportions of SARS-CoV-2 variants as well as the relationships between the origin and destination of each Omicron imported case were analyzed. Results: 4,946 sequences of imported cases were submitted from 27 provincial-level administrative divisions (PLADs), and the median submission interval was within 1 month after collection. In 3,851 Omicron sequences with good quality, 1 recombinant (XU) and 4 subvariants under monitoring (BA.4, BA.5, BA.2.12.1, and BA.2.13) were recorded, and 3 of them (BA.4, BA.5, and BA.2.12.1) caused local transmissions in the mainland of China later than that recorded in the surveillance. Omicron subvariants dominated in the first half of 2022 and shifted from BA.1 to BA.2 then to BA.4 and BA.5. The percentage of BA.2 in the imported SARS-CoV-2 surveillance data was far higher than that in the Global Initiative on Sharing All Influenza Data (GISAID). The imported cases from Hong Kong Special Administrative Region, China, accounted for 32.30% of Omicron cases sampled, and 98.71% of them were BA.2. Conclusions: The Omicron variant showed the intra-Omicron evolution in the first half of 2022, and all of the Omicron subvariants were introduced into the mainland of China multiple times from multiple different locations.

Genomic Surveillance for SARS-CoV-2 Variants of Concern from Imported COVID-19 Cases - the Mainland of China, 2021.

Introduction: After the epidemic in Wuhan City was brought under control in 2020, local outbreaks of coronavirus disease 2019 (COVID-19) in the mainland of China were mainly due to imported COVID-19 cases. The ongoing evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continued to generate new variants. Some have been designated as variants of concern (VOCs) by the World Health Organization (WHO). To better assess the role of imported SARS-CoV-2 surveillance and the prevalence of VOCs in 2021, the genomic surveillance data of SARS-CoV-2 from imported COVID-19 cases of 2021 in the mainland of China were analyzed. Methods: The analyses included the number of sequence submissions, time of sequence deposition, and time of detection of the VOCs in order to determine the timeliness and sensitivity of the surveillance. The proportions of VOCs were analyzed and compared with data from the Global Initiative of Sharing All Influenza Data (GISAID). Results: A total of 3,355 sequences of imported cases were submitted from 29 provincial-level administrative divisions, with differences in the number of sequence submissions and median time of sequence deposition. A total of 2,388 sequences with more than 90% genomic coverage were used for lineage analysis. The epidemic trend from Alpha to Delta to Omicron in imported cases was consistent with that in the GISAID. In addition, VOCs from imported cases were usually identified after WHO designation and before causing local outbreaks. Conclusions: The global distribution of SARS-CoV-2 VOCs changed rapidly in 2021. Robust genomic surveillance of the imported SARS-CoV-2 in the mainland of China is of great significance.

IOT based portable heart rate and SpO2 pulse oximeter.

Ever since the COVID-19 pandemic, the necessity of new,innovative medical devices to analyse and monitor the situation has become profound. With this in mind, we have developed an IOT based portable and cost-efficient heart rate and SpO2/level sensor device with efficient performance. The proposed system is equipped with an onboard OLED with simple internet connectivity, which publishes data on the OLED and to a HTML webpage. The salient features include its portability, user compatibility and is unique in its way of transmitting collected data online, making it achieve better results than the current available solutions in various ways. The system has on board a MAX30100 sensor(Pulse Oximeter sensor) and along with the IOT based microcontroller(WeMos D1 mini) enables the facility to monitor the real time health data of patients in real-time through a HTML page.

A tandem-repeat dimeric RBD protein-based covid-19 vaccine zf2001 protects mice and nonhuman primates.

Safe, efficacious, and deployable vaccines are urgently needed to control COVID-19 in the large-scale vaccination campaigns. We report here the preclinical studies of an approved protein subunit vaccine against COVID-19, ZF2001, which contains tandem-repeat dimeric receptor-binding domain (RBD) protein with alum-based adjuvant. We assessed vaccine immunogenicity and efficacy in both mice and non-human primates (NHPs). ZF2001 induced high levels of RBD-binding and SARS-CoV-2 neutralizing antibody in both mice and non-human primates, and elicited balanced TH1/TH2 cellular responses in NHPs. Two doses of ZF2001 protected Ad-hACE2-transduced mice against SARS-CoV-2 infection, as detected by reduced viral RNA and relieved lung injuries. In NHPs, vaccination of either 25 µg or 50 µg ZF2001 prevented infection with SARS-CoV-2 in lung, trachea, and bronchi, with milder lung lesions. No evidence of disease enhancement was observed in both animal models. ZF2001 has been approved for emergency use in China, Uzbekistan, Indonesia, and Columbia. The high safety, immunogenicity, and protection efficacy in both mice and NHPs found in this preclinical study was consistent with the results in human clinical trials.

Low-Cost Pulse Oximeter & Heart Rate Measurement for COVID Diagnosis

This paper presents a portable heart rate and SpO2 blood-oxygen-level monitoring system with robust performance. The system is designed to be user interactive and kept its architecture as minimalistic as possible. The system is small in size, and user compatibility is high compared with other conventional medical devices. This system is based on a MAX30100 sensor which can produce results with high accuracy. Anyone using this device can move during the monitoring of vital signs of the heart. This paper describes the practical application cases in which this type of system is mainly used where the end-user has size and mobility requirements in the first place. A custom-designed GUI is implemented on an OLED to display the measured sensor data in real-time.

A core-shell structured COVID-19 mRNA vaccine with favorable biodistribution pattern and promising immunity.

Although inoculation of COVID-19 vaccines has rolled out globally, there is still a critical need for safe and effective vaccines to ensure fair and equitable supply for all countries. Here, we report on the development of a highly efficacious mRNA vaccine, SW0123 that is composed of sequence-modified mRNA encoding the full-length SARS-CoV-2 Spike protein packaged in core-shell structured lipopolyplex (LPP) nanoparticles. SW0123 is easy to produce using a large-scale microfluidics-based apparatus. The unique core-shell structured nanoparticle facilitates vaccine uptake and demonstrates a high colloidal stability, and a desirable biodistribution pattern with low liver targeting effect upon intramuscular administration. Extensive evaluations in mice and nonhuman primates revealed strong immunogenicity of SW0123, represented by induction of Th1-polarized T cell responses and high levels of antibodies that were capable of neutralizing not only the wild-type SARS-CoV-2, but also a panel of variants including D614G and N501Y variants. In addition, SW0123 conferred effective protection in both mice and non-human primates upon SARS-CoV-2 challenge. Taken together, SW0123 is a promising vaccine candidate that holds prospects for further evaluation in humans.

Summary of the Detection Kits for SARS-CoV-2 Approved by the National Medical Products Administration of China and Their Application for Diagnosis of COVID-19.

The on-going global pandemic of coronavirus disease 2019 (COVID-19) caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been underway for about 11 months. Through November 20, 2020, 51 detection kits for SARS-CoV-2 nucleic acids (24 kits), antibodies (25 kits), or antigens (2 kits) have been approved by the National Medical Products Administration of China (NMPA). Convenient and reliable SARS-CoV-2 detection assays are urgently needed worldwide for strategic control of the pandemic. In this review, the detection kits approved in China are summarised and the three types of tests, namely nucleic acid, serological and antigen detection, which are available for the detection of COVID-19 are discussed in detail. The development of novel detection kits will lay the foundation for the control and prevention of the COVID-19 pandemic globally.

Development and effectiveness of pseudotyped SARS-CoV-2 system as determined by neutralizing efficiency and entry inhibition test in vitro.

With the development of the COVID-19 epidemic, there is an urgent need to establish a system for determining the effectiveness and neutralizing activity of vaccine candidates in biosafety level 2 (BSL-2) facilities. Previously, researchers had developed a pseudotyped virus system for SARS-CoV and MERS-CoV, based on HIV-1 core, bearing virus spike protein. During the development of a pseudotyped SARS-CoV-2 system, a eukaryotic expression plasmid expressing SARS-CoV-2 spike (S) protein was constructed and then co-transfected with HIV-1 based plasmid which containing the firefly luciferase reporter gene, into HEK293T cells to prepare the pseudotyped SARS-CoV-2 virus (ppSARS-2). We have successfully established the pseudotyped SARS-CoV-2 system for neutralization and entry inhibition assays. Huh7.5 cell line was found to be the most susceptible to our pseudotyped virus model. Different levels of neutralizing antibodies were detected in convalescent serum samples of COVID-19 patients using ppSARS-2. The recombinant, soluble, angiotensin-converting enzyme 2 protein was found to inhibit the entry of ppSARS-2 in Huh7.5 cells effectively. Furthermore, the neutralization results for ppSARS-2 were consistent with those of live SARS-CoV-2 and determined using the serum samples from convalescent patients. In conclusion, we have developed an easily accessible and reliable tool for studying the neutralizing efficiency of antibodies against SARS-CoV-2 and the entry process of the virus in a BSL-2 laboratory.

[Analysis on formula of Mongolian medicine for prevention of COVID-19].

The epidemic situation of coronavirus disease 2019(COVID-19) is developing rapidly in the world, and the influence is serious. In this study, the prescription of Mongolian medicine to prevent new type of COVID-19 was investigated. Based on the second edition and the third edition of COVID-19 Mongolian Medicine Prevention and Treatment Guidance Program issued by the Inner Mongolia Autonomous Region Health Commission, using Excel 2007, SPSS Modeler 18, SPSS Statistics 25, Cytoscape 3.7.1 statistical software as a tool, the association rules analysis and cluster analysis of Mongolian medicine included in the standard were carried out. Among the 45 prophylactic prescriptions included in the standard, a total of 34 high-frequency drugs using frequency ≥5 were used, of which Carthami Flos(21 times, 4.46%), Chebulae Fructus(20 times, 4.26%), Moschus(13 times, 2.77%), Myristicae Semen(12 times, 2.55%), Santali Albi Lignum(12 times, 2.55%), and Bovis Calculus(12 times, 2.55%) were the most common. The main drugs for the prevention of COVID-19 were Liang(13 times, 38.23%), Wen(9 times, 26.47%), the flavor was Ku(20 times, 34.48%), Xin(13 times, 22.41%), Gan(11 times, 18.97%), the most used drugs treating hot evil(99 times, 32.46%), treatment of "Heyi" drugs(51 times, 16.72%), treatment of "Badagan" drugs(40 times, 13.11%), treatment of "sticky" drugs(37 times, 12.13%), and a cough, eliminating phlegm and antiasthmatic(31 times, 10.16%), the association rule analysis found that the highest association intensity of the drug pair combination of 11. Clustering analysis using the cluster analysis of inter-group join method found a total of 8 categories. In this study, 45 prescriptions of Mongolian medicine for the prevention of COVID-19 were collec-ted and further analyzed, hoping to provide new ideas for clinical diagnosis and treatment.

Lack of antibody-mediated cross-protection between SARS-CoV-2 and SARS-CoV infections.

BACKGROUND: The novel coronavirus (SARS-CoV-2) shares approximately 80% whole genome sequence identity and 66% spike (S) protein identity with that of SARS-CoV. The cross-neutralization between these viruses is currently not well-defined. METHODS: Here, by using the live SARS-CoV-2 virus infection assay as well as HIV-1 based pseudotyped-virus carrying the spike (S) gene of the SARS-CoV-2 (ppSARS-2) and SARS-CoV (ppSARS), we examined whether infections with SARS-CoV and SARS-CoV-2 can induce cross-neutralizing antibodies. FINDINGS: We confirmed that SARS-CoV-2 infects cells via angiotensin converting enzyme 2 (ACE2), the functional receptor for SARS-CoV, and we also found that the recombinant receptor binding domain (RBD) of the S protein of SARS-CoV effectively inhibits ppSARS-2 entry in Huh7.5 cells. However, convalescent sera from SARS-CoV and SARS-CoV-2 patients showed high neutralizing activity only against the homologous virus, with no or limited cross-neutralization activity against the other pseudotyped virus. Similar results were also observed in vaccination studies in mice. INTERPRETATION: Our study demonstrates that although both SARS-CoV and SARS-CoV-2 use ACE2 as a cellular receptor, the neutralization epitopes are not shared by these two closely-related viruses, highlighting challenges towards developing a universal vaccine against SARS-CoV related viruses. FUNDING: This work was supported by the National Key Research and Development Program of China, the National Major Project for Control and Prevention of Infectious Disease in China, and the One Belt and One Road Major Project for infectious diseases.