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1.
Nonlinear Dyn ; 105(3): 2757-2773, 2021.
Article in English | MEDLINE | ID: covidwho-1330393

ABSTRACT

Multiple new variants of SARS-CoV-2 have been identified as the COVID-19 pandemic spreads across the globe. However, most epidemic models view the virus as static and unchanging and thus fail to address the consequences of the potential evolution of the virus. Here, we built a competitive susceptible-infected-removed (coSIR) model to simulate the competition between virus strains of differing severities or transmissibility under various virus control policies. The coSIR model predicts that although the virus is extremely unlikely to evolve into a "super virus" that causes an increased fatality rate, virus variants with less severe symptoms can lead to potential new outbreaks and can cost more lives over time. The present model also demonstrates that the protocols restricting the transmission of the virus, such as wearing masks and social distancing, are the most effective strategy in reducing total mortality. A combination of adequate testing and strict quarantine is a powerful alternative to policies such as mandatory stay-at-home orders, which may have an enormous negative impact on the economy. In addition, building Mobile Cabin Hospitals can be effective and efficient in reducing the mortality rate of highly infectious virus strains. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11071-021-06705-8.

2.
Virulence ; 12(1): 1209-1226, 2021 12.
Article in English | MEDLINE | ID: covidwho-1242086

ABSTRACT

New SARS-CoV-2 mutants have been continuously indentified with enhanced transmission ever since its outbreak in early 2020. As an RNA virus, SARS-CoV-2 has a high mutation rate due to the low fidelity of RNA polymerase. To study the single nucleotide polymorphisms (SNPs) dynamics of SARS-CoV-2, 158 SNPs with high confidence were identified by deep meta-transcriptomic sequencing, and the most common SNP type was C > T. Analyses of intra-host population diversity revealed that intra-host quasispecies' composition varies with time during the early onset of symptoms, which implicates viral evolution during infection. Network analysis of co-occurring SNPs revealed the most abundant non-synonymous SNP 22,638 in the S glycoprotein RBD region and 28,144 in the ORF8 region. Furthermore, SARS-CoV-2 variations differ in an individual's respiratory tissue (nose, throat, BALF, or sputum), suggesting independent compartmentalization of SARS-CoV-2 populations in patients. The positive selection analysis of the SARS-CoV-2 genome uncovered the positive selected amino acid G251V on ORF3a. Alternative allele frequency spectrum (AAFS) of all variants revealed that ORF8 could bear alternate alleles with high frequency. Overall, the results show the quasispecies' profile of SARS-CoV-2 in the respiratory tract in the first two months after the outbreak.


Subject(s)
Phylogeny , Polymorphism, Single Nucleotide , Quasispecies , SARS-CoV-2/classification , SARS-CoV-2/genetics , Adult , Aged , Aged, 80 and over , Alleles , COVID-19/virology , Computational Biology , Coronavirus Envelope Proteins/chemistry , Coronavirus Envelope Proteins/genetics , Female , Gene Frequency , Genome, Viral , HEK293 Cells , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Severity of Illness Index , Young Adult
3.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Article in English | MEDLINE | ID: covidwho-1117490

ABSTRACT

The pandemic of COVID-19, caused by SARS-CoV-2, is a major global health threat. Epidemiological studies suggest that bats (Rhinolophus affinis) are the natural zoonotic reservoir for SARS-CoV-2. However, the host range of SARS-CoV-2 and intermediate hosts that facilitate its transmission to humans remain unknown. The interaction of coronavirus with its host receptor is a key genetic determinant of host range and cross-species transmission. SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) as the receptor to enter host cells in a species-dependent manner. In this study, we characterized the ability of ACE2 from diverse species to support viral entry. By analyzing the conservation of five residues in two virus-binding hotspots of ACE2 (hotspot 31Lys and hotspot 353Lys), we predicted 80 ACE2 proteins from mammals that could potentially mediate SARS-CoV-2 entry. We chose 48 ACE2 orthologs among them for functional analysis, and showed that 44 of these orthologs-including domestic animals, pets, livestock, and animals commonly found in zoos and aquaria-could bind the SARS-CoV-2 spike protein and support viral entry. In contrast, New World monkey ACE2 orthologs could not bind the SARS-CoV-2 spike protein and support viral entry. We further identified the genetic determinant of New World monkey ACE2 that restricts viral entry using genetic and functional analyses. These findings highlight a potentially broad host tropism of SARS-CoV-2 and suggest that SARS-CoV-2 might be distributed much more widely than previously recognized, underscoring the necessity to monitor susceptible hosts to prevent future outbreaks.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , COVID-19/veterinary , Receptors, Virus/genetics , SARS-CoV-2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/genetics , COVID-19/metabolism , COVID-19/virology , Host Specificity , Humans , Pandemics/prevention & control , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Phylogeny , Protein Binding , Receptors, Virus/metabolism , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Viral Tropism , Viral Zoonoses/genetics , Viral Zoonoses/prevention & control , Viral Zoonoses/virology , Virus Attachment , Virus Internalization
4.
Sci Bull (Beijing) ; 66(9): 884-888, 2021 May 15.
Article in English | MEDLINE | ID: covidwho-1019467

ABSTRACT

Coronavirus disease-2019 (COVID-19) has become a major global epidemic. Facilitated by HTS2 technology, we evaluated the effects of 578 herbs and all 338 reported anti-COVID-19 TCM formulae on cytokine storm-related signaling pathways, and identified the key targets of the relevant pathways and potential active ingredients in these herbs. This large-scale transcriptional study innovatively combines HTS2 technology with bioinformatics methods and computer-aided drug design. For the first time, it systematically explores the molecular mechanism of TCM in regulating the COVID-19-related cytokine storm, providing an important scientific basis for elucidating the mechanism of action of TCM in treating COVID-19.

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