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1.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-325079

ABSTRACT

Ten emerging SARS-CoV-2 variants—B.1.1.298, B.1.1.7, B.1.351, P.1, P.2, B.1.429, B.1.525, B.1.526-1, B.1.526-2, B.1.1.318—and seven corresponding single amino acid mutations in the receptor-binding domain were examined using SARS-CoV-2 pseudovirus. The results indicate that the current SARS-CoV-2 variants do not increase infectivity among humans. The K417N/T, N501Y, or E484K-carrying variants exhibited increased abilities to infect to mouse ACE2-overexpressing cells. The activities of Furin, TMPRSS2, and cathepsin L were increased against most of the variants. RBD amino acid mutations comprising K417T/N, L452R, Y453F, S477N, E484K, and N501Y caused significant immune escape from 11 of 13 monoclonal antibodies. However, the resistance to neutralization by convalescent serum or vaccines was mainly caused by the E484K mutation, while the neutralization of E484K-carrying variants was decreased by 1.1–6.2-fold. The convalescent serum from B.1.1.7- and B.1.351-infected patients neutralized the variants themselves better than other SARS-CoV-2 variants.

2.
IEEE Communications Magazine ; 60(1):94-99, 2022.
Article in English | ProQuest Central | ID: covidwho-1685112

ABSTRACT

COVID-19 is a highly contagious coronavirus that has caused traumatic global havoc. By September 14, 2021, there were 224+ million confirmed cases and 4.6+ million fatalities world-wide [1]. Internet of Things (IoT)-based quarantine strategies effectively slow down and prevent COVID-19 transmission [2]. However, the unstan-dardized quarantine strategy may cause negative consequences. Typically, quarantine deactivates normal economic interactions, thus causing huge economic loss [3]. Moreover, the lack of versatility and resiliency also brings safety challenges on some occasions. In this investigation, a performance scoring quarantine index, referred to as QDex, is developed to provide guidance for a new concept of dynamic geofencing quarantine directive. QDex evaluation features adaptive dynamic geofencing (QEDG) for quarantine. In QEDG, QDex is newly defined to evaluate the dynamic geofencing in relation to epidemic control and economic loss. They are represented by two formulated indicators, namely the transmission risk (TR) and the active profit (AP), which are related to the isolator bio status (e.g., body temperature). Based on the evaluation results of TR and AP, QEDG provides a proper geofencing indication for quarantine, which decreases epidemic transmission and restores economic recovery. The requirement-based applicable communication technologies for QEDG are discussed and analyzed, and two typical use cases are included. Finally, the limitations and challenges of QEDG are discussed.

3.
Emerg Microbes Infect ; 11(1): 552-555, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1655962

ABSTRACT

We identified an individual who was coinfected with two SARS-CoV-2 variants of concern, the Beta and Delta variants. The ratio of the relative abundance between the two variants was maintained at 1:9 (Beta:Delta) in 14 days. Furthermore, possible evidence of recombinations in the Orf1ab and Spike genes was found.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Recombination, Genetic , Spike Glycoprotein, Coronavirus/genetics
5.
Commun Biol ; 4(1): 1196, 2021 10 13.
Article in English | MEDLINE | ID: covidwho-1467140

ABSTRACT

Emerging mutations in SARS-CoV-2 cause several waves of COVID-19 pandemic. Here we investigate the infectivity and antigenicity of ten emerging SARS-CoV-2 variants-B.1.1.298, B.1.1.7(Alpha), B.1.351(Beta), P.1(Gamma), P.2(Zeta), B.1.429(Epsilon), B.1.525(Eta), B.1.526-1(Iota), B.1.526-2(Iota), B.1.1.318-and seven corresponding single amino acid mutations in the receptor-binding domain using SARS-CoV-2 pseudovirus. The results indicate that the pseudovirus of most of the SARS-CoV-2 variants (except B.1.1.298) display slightly increased infectivity in human and monkey cell lines, especially B.1.351, B.1.525 and B.1.526 in Calu-3 cells. The K417N/T, N501Y, or E484K-carrying variants exhibit significantly increased abilities to infect mouse ACE2-overexpressing cells. The activities of furin, TMPRSS2, and cathepsin L are increased against most of the variants. RBD amino acid mutations comprising K417T/N, L452R, Y453F, S477N, E484K, and N501Y cause significant immune escape from 11 of 13 monoclonal antibodies. However, the resistance to neutralization by convalescent serum or vaccines elicited serum is mainly caused by the E484K mutation. The convalescent serum from B.1.1.7- and B.1.351-infected patients neutralized the variants themselves better than other SARS-CoV-2 variants. Our study provides insights regarding therapeutic antibodies and vaccines, and highlights the importance of E484K mutation.


Subject(s)
COVID-19/virology , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Animals , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/immunology , COVID-19/immunology , COVID-19/therapy , Cell Line , HEK293 Cells , Humans , Immunization, Passive/methods , Mammals/immunology , Mice , Mutation , Pandemics , Primates/immunology , Protein Binding , Tropism/genetics
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