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1.
Brittonia ; 75(2): 180-190, 2023.
Article in English | MEDLINE | ID: covidwho-20235429

ABSTRACT

Macrolobium paulobocae is presented as a new species of the legume subfamily Detarioideae. It is restricted to seasonally flooded igapó forests in the Central Amazon. We provide a description, illustration, photographs, and a distribution map of the new species, as well as a table of comparative morphology with similar, likely phylogenetically related species. The epithet is in honor of Paulo Apóstolo Costa Lima Assunção, or Paulo Boca, a great Amazonian botanist, victim of COVID-19 in January 2021.

2.
3.
Health Sci Rep ; 6(4): e1209, 2023 Apr.
Article in English | MEDLINE | ID: covidwho-2302228

ABSTRACT

Background and Aims: Since the beginning of the SARS-CoV-2 pandemic, multiple new variants have emerged posing an increased risk to global public health. This study aimed to investigate SARS-CoV-2 variants, their temporal dynamics, infection rate (IFR) and case fatality rate (CFR) in Bangladesh by analyzing the published genomes. Methods: We retrieved 6610 complete whole genome sequences of the SARS-CoV-2 from the GISAID (Global Initiative on Sharing all Influenza Data) platform from March 2020 to October 2022, and performed different in-silico bioinformatics analyses. The clade and Pango lineages were assigned by using Nextclade v2.8.1. SARS-CoV-2 infections and fatality data were collected from the Institute of Epidemiology Disease Control and Research (IEDCR), Bangladesh. The average IFR was calculated from the monthly COVID-19 cases and population size while average CFR was calculated from the number of monthly deaths and number of confirmed COVID-19 cases. Results: SARS-CoV-2 first emerged in Bangladesh on March 3, 2020 and created three pandemic waves so far. The phylogenetic analysis revealed multiple introductions of SARS-CoV-2 variant(s) into Bangladesh with at least 22 Nextstrain clades and 107 Pangolin lineages with respect to the SARS-CoV-2 reference genome of Wuhan/Hu-1/2019. The Delta variant was detected as the most predominant (48.06%) variant followed by Omicron (27.88%), Beta (7.65%), Alpha (1.56%), Eta (0.33%) and Gamma (0.03%) variant. The overall IFR and CFR from circulating variants were 13.59% and 1.45%, respectively. A time-dependent monthly analysis showed significant variations in the IFR (p = 0.012, Kruskal-Wallis test) and CFR (p = 0.032, Kruskal-Wallis test) throughout the study period. We found the highest IFR (14.35%) in 2020 while Delta (20A) and Beta (20H) variants were circulating in Bangladesh. Remarkably, the highest CFR (1.91%) from SARS-CoV-2 variants was recorded in 2021. Conclusion: Our findings highlight the importance of genomic surveillance for careful monitoring of variants of concern emergence to interpret correctly their relative IFR and CFR, and thus, for implementation of strengthened public health and social measures to control the spread of the virus. Furthermore, the results of the present study may provide important context for sequence-based inference in SARS-CoV-2 variant(s) evolution and clinical epidemiology beyond Bangladesh.

4.
Emerg Infect Dis ; 29(3): 585-589, 2023 03.
Article in English | MEDLINE | ID: covidwho-2278518

ABSTRACT

Middle East respiratory syndrome coronavirus (MERS-CoV) clade B viruses are found in camelids and humans in the Middle East, but clade C viruses are not. We provide experimental evidence for extended shedding of MERS-CoV clade B viruses in llamas, which might explain why they outcompete clade C strains in the Arabian Peninsula.


Subject(s)
Camelids, New World , Coronavirus Infections , Herpesvirus 1, Cercopithecine , Middle East Respiratory Syndrome Coronavirus , Animals , Humans , Virus Shedding , Camelus
5.
Cureus ; 15(2): e34653, 2023 Feb.
Article in English | MEDLINE | ID: covidwho-2275849

ABSTRACT

The significant increase in monkeypox cases that was reported at the beginning of 2022 was notable. The resurgence of viral zoonosis is especially concerning, given the current and recent COVID-19 epidemic. There are worries that a new pandemic may be beginning due to the virus that causes monkeypox spreading so quickly. This article aimed to provide an overview of the epidemiology, pathogenesis, and clinical symptoms of monkeypox. It has been known that monkeypox was primarily prevalent in Central and West Africa, but in recent years, cases of monkeypox infections have been reported around the world. The transmission of the infection to humans has been connected to exposure to a diseased animal or person's excretions and secretions. Various studies indicate that monkeypox clinically manifests as fever, fatigue, and a rash of smallpox-like lesions and can cause various complications, including pneumonia, encephalitis, and sepsis, which, when not properly managed, can lead to death. Those living in remote and forested areas, taking care of individuals infected with monkeypox, and trading and taking care of exotic animals are some of the risk factors for monkeypox. Men having sex with men are also at higher risk of contracting monkeypox. When dealing with individuals who have high-risk factors and come with new-onset progressive rashes, it is necessary for clinicians to highly suspect monkeypox. This review will serve as reference material and a supplement to the existing literature that will assist in the proper management and prevention of monkeypox.

6.
Genes (Basel) ; 14(3)2023 03 09.
Article in English | MEDLINE | ID: covidwho-2275547

ABSTRACT

The emergence of the Coronavirus Disease 2019 (COVID-19) pandemic has fostered the use of high-throughput techniques to sequence the entire severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome and track its evolution. The present study proposes a rapid and relatively less expensive sequencing protocol for 384 samples by adapting the use of an Illumina NovaSeq library to an Illumina MiSeq flow cell instrument. The SARS-CoV-2 genome sequences obtained with Illumina NovaSeq and those obtained using MiSeq instruments were compared with the objective to validate the new, modified protocol. A total of 356 (94.6%) samples yielded interpretable sequences using the modified Illumina COVIDSeq protocol, with an average coverage of 91.6%. By comparison, 357 (94.9%) samples yielded interpretable sequences with the standard COVIDSeq protocol, with an average coverage of 95.6%. Our modified COVIDSeq protocol could save 14,155 euros per run and yield results from 384 samples in 53.5 h, compared to four times 55.5 h with the standard Illumina MiSeq protocol. The modified COVIDSeq protocol thus provides high quality results comparable to those obtained with the standard COVIDSeq protocol, four times faster, while saving money.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/genetics , Whole Genome Sequencing/methods , Gene Library , Genome, Viral
7.
J Formos Med Assoc ; 2022 Sep 26.
Article in English | MEDLINE | ID: covidwho-2241581

ABSTRACT

he first imported case of monkeypox in Taiwan was diagnosed in an Asian man with HIV-1 infection and asymptomatic COVID-19, returning from Germany. Atypical presentations included asynchronous skin lesions, anogenital lesions and prominent inguinal lymphadenopathy. Whole genomic sequence alignment indicate that the Taiwan strain clustered together with human monkeypox virus West African clade B.1, currently circulating in Europe. Prompt diagnosis and infection control measures are crucial to mitigate the spread of monkeypox.

8.
Health Sci Rep ; 6(1): e1052, 2023 Jan.
Article in English | MEDLINE | ID: covidwho-2227329

ABSTRACT

Background and Aim: Characterization of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) based on analyzing the evolution and mutations of viruses is crucial for tracking viral infections, potential mutants, and other pathogens. The purpose was to study the complete sequences of SARS-CoV-2 to reveal genetic distance and mutation rate among different provinces of Iran. Methods: As of March 2020-April 2021, a total of 131 SARS-CoV-2 whole genome sequences submitted from Tehran and 133 SARS-CoV-2 full-length sequences from 24 cities with high coverage submitted to EpiCoV GISAID database were analyzed to infer clades and mutation annotation compared with the wild-type variant Wuhan-Hu-1. Results: The results of variant annotation were revealed 11,204 and 9468 distinct genomes were identified among the samples from different cities and Tehran, respectively. The phylogenetic analysis of genomic sequences showed the presence of eight GISAID clades, namely GH, GR, O, GRY, G, GK, L, and GV, and six Nextstrain clades; that is, 19A, 20A, 20B, 20I (alpha, V1), 20H (Beta, V2), and 21I (Delta) in Iran. The GH (GISAID clade), 20A (Nextstrain clade), and B.1 (Pango lineage) were predominant in Iran. Notably, analysis of the spike protein revealed D614G mutation (S_D614G) in 56% of the sequences. Also, the delta variant of the coronavirus, the super-infectious strain that was first identified among the sequences submitted from the southern cities of the country such as Zahedan, Yazd and Bushehr, and most likely from these places to other cities of Iran as well has expanded. Conclusions: Our results indicate that most of the circulated viruses in Iran in the early time of the pandemic had collected in eight GISAID clades. Therefore, a continuous and extensive genome sequence analysis would be necessary to understand the genomic epidemiology of SARS-CoV-2 in Iran.

9.
Pathogens ; 11(11)2022 Nov 21.
Article in English | MEDLINE | ID: covidwho-2116104

ABSTRACT

The circulation of seasonal influenza in 2020-2021 around the world was drastically reduced after the start of the COVID-19 pandemic and the implementation of mitigation strategies. The influenza virus circulation reemerged in 2021-2022 with the global spread of the new genetic clade 3C.2a1b.2a.2 of A(H3N2) viruses. The purpose of this study was to characterize influenza viruses in the 2021-2022 season in Russia and to analyze the receptor specificity properties of the 3C.2a1b.2a.2 A(H3N2) viruses. Clinical influenza samples were collected at the local Sanitary-and-Epidemiological Centers of Rospotrebnadzor. Whole genome sequencing was performed using NGS. The receptor specificity of hemagglutinin was evaluated using molecular modeling and bio-layer interferometry. Clinical samples from 854 cases of influenza A and B were studied; A(H3N2) viruses were in the majority of the samples. All genetically studied A(H3N2) viruses belonged to the new genetic clade 3C.2a1b.2a.2. Molecular modeling analysis suggested a higher affinity of hemagglutinin of 3C.2a1b.2a.2. A(H3N2) viruses to the α2,6 human receptor. In vitro analysis using a trisaccharide 6'-Sialyl-N-acetyllactosamine receptor analog did not resolve the differences in the receptor specificity of 3C.2a1b.2a.2 clade viruses from viruses belonging to the 3C.2a1b.2a.1 clade. Further investigation of the A(H3N2) viruses is required for the evaluation of their possible adaptive advantages. Constant monitoring and characterization of influenza are critical for epidemiological analysis.

10.
Int Immunopharmacol ; 112: 109224, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-2076214

ABSTRACT

In the worrisome scenarios of various waves of SARS-CoV-2 pandemic, a comprehensive bioinformatics pipeline is essential to analyse the virus genomes in order to understand its evolution, thereby identifying mutations as signature SNPs, conserved regions and subsequently to design epitope based synthetic vaccine. We have thus performed multiple sequence alignment of 4996 Indian SARS-CoV-2 genomes as a case study using MAFFT followed by phylogenetic analysis using Nextstrain to identify virus clades. Furthermore, based on the entropy of each genomic coordinate of the aligned sequences, conserved regions are identified. After refinement of the conserved regions, based on its length, one conserved region is identified for which the primers and probes are reported for virus detection. The refined conserved regions are also used to identify T-cell and B-cell epitopes along with their immunogenic and antigenic scores. Such scores are used for selecting the most immunogenic and antigenic epitopes. By executing this pipeline, 40 unique signature SNPs are identified resulting in 23 non-synonymous signature SNPs which provide 28 amino acid changes in protein. On the other hand, 12 conserved regions are selected based on refinement criteria out of which one is selected as the potential target for virus detection. Additionally, 22 MHC-I and 21 MHC-II restricted T-cell epitopes with 10 unique HLA alleles each and 17 B-cell epitopes are obtained for 12 conserved regions. All the results are validated both quantitatively and qualitatively which show that from genetic variability to synthetic vaccine design, the proposed pipeline can be used effectively to combat SARS-CoV-2.


Subject(s)
COVID-19 , Viral Vaccines , Humans , SARS-CoV-2/genetics , Epitopes, B-Lymphocyte , Epitopes, T-Lymphocyte , COVID-19 Vaccines/genetics , Computational Biology , Phylogeny , COVID-19/prevention & control , Immunogenicity, Vaccine , Vaccines, Synthetic/genetics , Amino Acids
11.
Microorganisms ; 10(10)2022 Oct 12.
Article in English | MEDLINE | ID: covidwho-2071646

ABSTRACT

Pathogens including viruses evolve in tandem with diversity in their animal and human hosts. For SARS-coV2, the focus is generally for understanding such coevolution on the virus spike protein, since it demonstrates high mutation rates compared to other genome regions, particularly in the receptor-binding domain (RBD). Viral sequences of the SARS-coV2 19B (S) clade and variants of concern from different continents were investigated, with a focus on the A.29 lineage, which presented with different mutational patterns within the 19B (S) lineages in order to learn more about how SARS-coV2 may have evolved and adapted to widely diverse populations globally. Results indicated that SARS-coV2 went through evolutionary constrains and intense selective pressure, particularly in Africa. This was manifested in a departure from neutrality with excess nonsynonymous mutations and a negative Tajima D consistent with rapid expansion and directional selection as well as deletion and deletion-frameshifts in the N-terminal domain (NTD region) of the spike protein. In conclusion, we hypothesize that viral transmission during epidemics through populations of diverse genomic structures and marked complexity may be a significant factor for the virus to acquire distinct patterns of mutations within these populations in order to ensure its survival and fitness, explaining the emergence of novel variants and strains.

12.
Front Med (Lausanne) ; 9: 1001022, 2022.
Article in English | MEDLINE | ID: covidwho-2065583

ABSTRACT

Countries around the world are gearing for the transition of the coronavirus disease 2019 (COVID-19) from pandemic to endemic phase but the emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants could lead to a prolonged pandemic. SARS-CoV-2 has continued to evolve as it optimizes its adaptation to the human host and the successive waves of COVID-19 have been linked to the explosion of particular variant of concern. As the genetic diversity and epidemiological landscape of SARS-CoV-2 differ from country to country, this study aims to provide insights into the variants that are circulating in Malaysia. Whole genome sequencing was performed for 204 SARS-CoV-2 from COVID-19 cases and an additional 18,667 SARS-CoV-2 genome sequences were retrieved from the GISAID EpiCoV database for clade, lineage and genetic variation analyses. Complete genome sequences with high coverage were then used for phylogeny investigation and the resulting phylogenetic tree was constructed from 8,716 sequences. We found that the different waves of COVID-19 in Malaysia were dominated by different clades with the L and O clade for first and second wave, respectively, whereas the progressive replacement by G, GH, and GK of the GRA clade were observed in the subsequence waves. Continuous monitoring of the genetic diversity of SARS-CoV-2 is important to identify the emergence and dominance of new variant in different locality so that the appropriate countermeasures can be taken to effectively contain the spread of SARS-CoV-2.

13.
Euro Surveill ; 27(38)2022 09.
Article in English | MEDLINE | ID: covidwho-2054865

ABSTRACT

Influenza virus circulation virtually ceased in Canada during the COVID-19 pandemic, re-emerging with the relaxation of restrictions in spring 2022. Using a test-negative design, the Canadian Sentinel Practitioner Surveillance Network reports 2021/22 vaccine effectiveness of 36% (95% CI: -38 to 71) against late-season illness due to influenza A(H3N2) clade 3C.2a1b.2a.2 viruses, considered antigenically distinct from the 3C.2a1b.2a.1 vaccine strain. Findings reinforce the World Health Organization's decision to update the 2022/23 northern hemisphere vaccine to a more representative A(H3N2) clade 3C.2a1b.2a.2 strain.


Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , Canada/epidemiology , Humans , Influenza A Virus, H3N2 Subtype , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pandemics/prevention & control , Vaccine Efficacy
14.
Front Med (Lausanne) ; 9: 869818, 2022.
Article in English | MEDLINE | ID: covidwho-2009875

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is believed to have originated in Wuhan City, Hubei Province, China, in December 2019. Infection with this highly dangerous human-infecting coronavirus via inhalation of respiratory droplets from SARS-CoV-2 carriers results in coronavirus disease 2019 (COVID-19), which features clinical symptoms such as fever, dry cough, shortness of breath, and life-threatening pneumonia. Several COVID-19 waves arose in Taiwan from January 2020 to March 2021, with the largest outbreak ever having a high case fatality rate (CFR) (5.95%) between May and June 2021. In this study, we identified five 20I (alpha, V1)/B.1.1.7/GR SARS-CoV-2 (KMUH-3 to 7) lineage viruses from COVID-19 patients in this largest COVID-19 outbreak. Sequence placement analysis using the existing SARS-CoV-2 phylogenetic tree revealed that KMUH-3 originated from Japan and that KMUH-4 to KMUH-7 possibly originated via local transmission. Spike mutations M1237I and D614G were identified in KMUH-4 to KMUH-7 as well as in 43 other alpha/B.1.1.7 sequences of 48 alpha/B.1.1.7 sequences deposited in GISAID derived from clinical samples collected in Taiwan between 20 April and July. However, M1237I mutation was not observed in the other 12 alpha/B.1.1.7 sequences collected between 26 December 2020, and 12 April 2021. We conclude that the largest COVID-19 outbreak in Taiwan between May and June 2021 was initially caused by the alpha/B.1.1.7 variant harboring spike D614G + M1237I mutations, which was introduced to Taiwan by China Airlines cargo crew members. To our knowledge, this is the first documented COVID-19 outbreak caused by alpha/B.1.1.7 variant harboring spike M1237I mutation thus far. The largest COVID-19 outbreak in Taiwan resulted in 13,795 cases and 820 deaths, with a high CFR, at 5.95%, accounting for 80.90% of all cases and 96.47% of all deaths during the first 2 years. The high CFR caused by SARS-CoV-2 alpha variants in Taiwan can be attributable to comorbidities and low herd immunity. We also suggest that timely SARS-CoV-2 isolation and/or sequencing are of importance in real-time epidemiological investigations and in epidemic prevention. The impact of G614G + M1237I mutations in the spike gene on the SARS-CoV-2 virus spreading as well as on high CFR remains to be elucidated.

15.
Trop Med Infect Dis ; 7(8)2022 Aug 20.
Article in English | MEDLINE | ID: covidwho-1997799

ABSTRACT

With the progression of the global SARS-CoV-2 pandemic, the new variants have become more infectious and continue spreading at a higher rate than pre-existing ones. Thus, we conducted a study to explore the epidemiology of emerging variants of SARS-CoV-2 that circulated in Bangladesh from December 2020 to September 2021, representing the 2nd and 3rd waves. We collected new cases and deaths per million daily data with the reproduction rate. We retrieved 928 SARS-CoV-2 sequences from GISAID and performed phylogenetic tree construction and mutation analysis. Case counts were lower initially at the end of 2020, during January-February and April-May 2021, whereas the death toll reached the highest value of 1.587 per million on the first week of August and then started to decline. All the variants (α, ß, δ, η) were prevalent in the capital city, Dhaka, with dispersion to large cities, such as Sylhet and Chattogram. The B.1.1.25 lineage was prevalent during December 2020, but the B.1.617.2/δ variant was later followed by the B.1.351/ß variant. The phylogeny revealed that the various strains found in Bangladesh could be from numerous countries. The intra-cluster and inter-cluster communication began in Bangladesh soon after the virus arrived. The prominent amino acid substitution was D614G from December 2020 to July 2021 (93.5 to 100%). From February-April, one of the VOC's important mutations, N501Y substitution, was also estimated at 51.8%, 76.1%, and 65.1% for the α, ß and γ variants, respectively. The γ variant's unique mutation K417T was detected only at 1.8% in February. Another frequent mutation was P681R, a salient feature of the δ variant, detected in June (88.2%) and July (100%). Furthermore, only one γ variant was detected during the entire second and third wave, whereas no η variant was observed in this period. This rapid growth in the number of variants identified across Bangladesh shows virus adaptation and a lack of strict quarantine, prompting periodic genomic surveillance to foresee the spread of new variants, if any, and to take preventive measures as soon as possible.

16.
Viruses ; 14(8)2022 07 29.
Article in English | MEDLINE | ID: covidwho-1969505

ABSTRACT

Whole-genome sequencing has become an essential tool for real-time genomic surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) worldwide. The handling of raw next-generation sequencing (NGS) data is a major challenge for sequencing laboratories. We developed an easy-to-use web-based application (EPISEQ SARS-CoV-2) to analyse SARS-CoV-2 NGS data generated on common sequencing platforms using a variety of commercially available reagents. This application performs in one click a quality check, a reference-based genome assembly, and the analysis of the generated consensus sequence as to coverage of the reference genome, mutation screening and variant identification according to the up-to-date Nextstrain clade and Pango lineage. In this study, we validated the EPISEQ SARS-CoV-2 pipeline against a reference pipeline and compared the performance of NGS data generated by different sequencing protocols using EPISEQ SARS-CoV-2. We showed a strong agreement in SARS-CoV-2 clade and lineage identification (>99%) and in spike mutation detection (>99%) between EPISEQ SARS-CoV-2 and the reference pipeline. The comparison of several sequencing approaches using EPISEQ SARS-CoV-2 revealed 100% concordance in clade and lineage classification. It also uncovered reagent-related sequencing issues with a potential impact on SARS-CoV-2 mutation reporting. Altogether, EPISEQ SARS-CoV-2 allows an easy, rapid and reliable analysis of raw NGS data to support the sequencing efforts of laboratories with limited bioinformatics capacity and those willing to accelerate genomic surveillance of SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnosis , Genome, Viral , High-Throughput Nucleotide Sequencing/methods , Humans , Mutation , SARS-CoV-2/genetics
17.
BMC Infect Dis ; 22(1): 558, 2022 Jun 19.
Article in English | MEDLINE | ID: covidwho-1962753

ABSTRACT

BACKGROUND: A global pandemic has been declared for coronavirus disease 2019 (COVID-19), which has serious impacts on human health and healthcare systems in the affected areas, including Vietnam. None of the previous studies have a framework to provide summary statistics of the virus variants and assess the severity associated with virus proteins and host cells in COVID-19 patients in Vietnam. METHOD: In this paper, we comprehensively investigated SARS-CoV-2 variants and immune responses in COVID-19 patients. We provided summary statistics of target sequences of SARS-CoV-2 in Vietnam and other countries for data scientists to use in downstream analysis for therapeutic targets. For host cells, we proposed a predictive model of the severity of COVID-19 based on public datasets of hospitalization status in Vietnam, incorporating a polygenic risk score. This score uses immunogenic SNP biomarkers as indicators of COVID-19 severity. RESULT: We identified that the Delta variant of SARS-CoV-2 is most prevalent in southern areas of Vietnam and it is different from other areas in the world using various data sources. Our predictive models of COVID-19 severity had high accuracy (Random Forest AUC = 0.81, Elastic Net AUC = 0.7, and SVM AUC = 0.69) and showed that the use of polygenic risk scores increased the models' predictive capabilities. CONCLUSION: We provided a comprehensive analysis for COVID-19 severity in Vietnam. This investigation is not only helpful for COVID-19 treatment in therapeutic target studies, but also could influence further research on the disease progression and personalized clinical outcomes.


Subject(s)
COVID-19 Drug Treatment , COVID-19 , Coronavirus Infections , Pneumonia, Viral , Betacoronavirus , COVID-19/epidemiology , Genome-Wide Association Study , Humans , SARS-CoV-2/genetics , Vietnam/epidemiology
18.
Saudi J Biol Sci ; 29(9): 103372, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-1937146

ABSTRACT

The world has been combating different variants of SARS-COV-19 since its first outbreak in Wuhan city. SARS-COV-19 is caused by the coronavirus. The corona virus mutates and becomes more transmissible than earlier variants as the day passes. Till 24 November 2021, SARS-COV-19 has four variants Alpha, Beta, Gamma, and Delta, respectively. Among them, the delta variant caused severe havoc across the world. South Africa registered a new variant with the World Health Organization (WHO) on 24 November 2021, which is much more transmissible than previous variants. The WHO classified it as a variant of concern (VOC) on 26 November 2021 and called it the Greek letter Omicron (B.1.1.529), the fifteenth letter in the alphabet. Here a serious attempt was made to comprehend the omicron variant's origin, nomenclature, characteristics, mutations, the difference between delta and omicron variant, epidemiology, transmission, clinical features, impact on immunity, immune evasion, vaccines efficacy, etc.

19.
Geroscience ; 2022 Jul 13.
Article in English | MEDLINE | ID: covidwho-1930523

ABSTRACT

The ongoing SARS-CoV-2 evolution process has generated several variants due to its continuous mutations, making pandemics more critical. The present study illustrates SARS-CoV-2 evolution and its emerging mutations in five directions. First, the significant mutations in the genome and S-glycoprotein were analyzed in different variants. Three linear models were developed with the regression line to depict the mutational load for S-glycoprotein, total genome excluding S-glycoprotein, and whole genome. Second, the continent-wide evolution of SARS-CoV-2 and its variants with their clades and divergence were evaluated. It showed the region-wise evolution of the SARS-CoV-2 variants and their clustering event. The major clades for each variant were identified. One example is clade 21K, a major clade of the Omicron variant. Third, lineage dynamics and comparison between SARS-CoV-2 lineages across different countries are also illustrated, demonstrating dominant variants in various countries over time. Fourth, gene-wise mutation patterns and genetic variability of SARS-CoV-2 variants across various countries are illustrated. High mutation patterns were found in the ORF10, ORF6, S, and low mutation pattern E genes. Finally, emerging AA point mutations (T478K, L452R, N501Y, S477N, E484A, Q498R, and Y505H), their frequencies, and country-wise occurrence were identified, and the highest event of two mutations (T478K and L452R) was observed.

20.
Virology ; 573: 84-95, 2022 08.
Article in English | MEDLINE | ID: covidwho-1895491

ABSTRACT

The world health organization has announced that SARS-CoV-2 Omicron variant (B.1.1.529), including the three versions; 21K (BA.1), 21L (BA.2) and 21M (BA.3) as a variant of concern (VOC) on November 2022. In this study, we used the specialized computational platforms to predict the stability and flexibility of the spike protein of Omicron. The aim of this study was to investigate the expected effect of Omicron spike mutations on its physiochemical properties. Findings of this study revealed 16 stabilizing mutations that might explain a newly gained environmental stability. We expect the new mutations to play a crucial role in changing the physiochemical properties of epitopes of the spike protein. The notable finding of SuerPose work was the potential linear B-cells epitope G252 → S255 that has been changed in the spike protein of the Omicron 21L to a helix structure which might confer an escape from human monoclonal antibodies.


Subject(s)
COVID-19 , Epitopes, B-Lymphocyte , Amino Acid Sequence , Antibodies, Viral , Epitopes, B-Lymphocyte/genetics , Humans , Membrane Glycoproteins/genetics , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Viral Envelope Proteins/genetics
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