Omicron SARS-CoV-2 variant: a new chapter in the COVID-19 pandemic

The Lancet, Journal Year: 2021, Volume and Issue: 398(10317), P. 2126 - 2128

Published: Dec. 1, 2021

Language: Английский

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Infectious viral load in unvaccinated and vaccinated individuals infected with ancestral, Delta or Omicron SARS-CoV-2

Nature Medicine, Journal Year: 2022, Volume and Issue: 28(7), P. 1491 - 1500

Published: April 8, 2022

Language: Английский

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SARS-CoV-2 breakthrough infections in vaccinated individuals: measurement, causes and impact

Nature reviews. Immunology, Journal Year: 2021, Volume and Issue: 22(1), P. 57 - 65

Published: Dec. 7, 2021

Language: Английский

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A bacterial extracellular vesicle‐based intranasal vaccine against SARS‐CoV‐2 protects against disease and elicits neutralizing antibodies to wild‐type and Delta variants

Journal of Extracellular Vesicles, Journal Year: 2022, Volume and Issue: 11(3)

Published: March 1, 2022

Several vaccines have been introduced to combat the coronavirus infectious disease-2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome 2 (SARS-CoV-2). Current SARS-CoV-2 include mRNA-containing lipid nanoparticles or adenoviral vectors that encode Spike (S) protein of SARS-CoV-2, inactivated virus, subunits. Despite growing success in worldwide vaccination efforts, additional capabilities may be needed future address issues such as stability and storage requirements, need for vaccine boosters, desirability different routes administration, emergence variants Delta variant. Here, we present a novel, well-characterized candidate based on extracellular vesicles (EVs) Salmonella typhimurium are decorated with mammalian cell culture-derived receptor-binding domain (RBD). RBD-conjugated outer membrane (RBD-OMVs) were used immunize golden Syrian hamster (Mesocricetus auratus) model COVID-19. Intranasal immunization resulted high titres blood anti-RBD IgG well detectable mucosal responses. Neutralizing antibody activity against wild-type was evident all vaccinated subjects. Upon challenge live hamsters immunized RBD-OMV, but not animals unconjugated OMVs vehicle control, avoided body mass loss, had lower virus bronchoalveolar lavage fluid, experienced less lung pathology. Our results emphasize value versatility OMV-based approaches.

Language: Английский

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Severity of Acute COVID-19 in Children <18 Years Old March 2020 to December 2021

PEDIATRICS, Journal Year: 2022, Volume and Issue: 149(4)

Published: March 24, 2022

This national study evaluated trends in illness severity among 82 798 children with coronavirus disease 2019 from March 1, 2020, to December 30, 2021.

Language: Английский

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SARS-CoV-2 Variants: Genetic Insights, Epidemiological Tracking, and Implications for Vaccine Strategies

International Journal of Molecular Sciences, Journal Year: 2025, Volume and Issue: 26(3), P. 1263 - 1263

Published: Jan. 31, 2025

The emergence of SARS-CoV-2 variants has significantly impacted the global response to COVID-19 pandemic. This review examines genetic diversity variants, their roles in epidemiological tracking, and influence on viral fitness. Variants concern (VOCs) such as Alpha, Beta, Gamma, Delta, Omicron have demonstrated increased transmissibility, altered pathogenicity, potential resistance neutralizing antibodies. Epidemiological tracking these is crucial for understanding spread, informing public health interventions, guiding vaccine development. also explores how specific mutations spike protein other genomic regions contribute fitness, affecting replication efficiency, immune escape, transmission dynamics. By integrating surveillance data with clinical findings, this provides a comprehensive overview ongoing evolution its implications strategies new

Language: Английский

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The emergence of new SARS-CoV-2 variant (Omicron) and increasing calls for COVID-19 vaccine boosters-The debate continues

Travel Medicine and Infectious Disease, Journal Year: 2021, Volume and Issue: 45, P. 102246 - 102246

Published: Dec. 21, 2021

Omicron Variant of concern SARS-CoV-2 Booster dose Emerging virusesThe emergence highly mutated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant (B.1.1.529)has ushered panic responses around the world due to its contagious and vaccine escape mutations.This has been designated as a (VOC) by World Health Organization (WHO) [1,2].Since January 2021, multiple virus variants have emerged become dominant in many countries [Table 1].The these VOCs (Alpha, Beta, Gamma, Delta) was responsible for new waves infections across entire [3].The Delta reported increased transmissibility, higher viral load [4] high rates reinfection [5].Because ability from natural immunity [6], it became globally variant.The VOC transformed notion COVID-19 endgame created fresh discussion over-vaccination effectiveness ongoing booster campaign an already COVID-19-weary world.Compared other VOCs, this variation unusually carries exceptionally number mutations (50) on spike (S) protein, major antigenic target antibodies produced or immunization.This led scientific community investigate how much could undermine existing vaccines.The knows little about Omicron's infectivity, breakthrough, antibody resistance, reliable experimental results labs will take few weeks come out.Although conclusive immunological clinical data are not yet available, early genomic show immune evasion capabilities, fast transmission ability, rate, severity [7].This triggered calls intensify vaccination programmes, including doses [8]. 1. "Omicron" escalates debate: boost

Language: Английский

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SARS-CoV-2 variants – Evolution, spike protein, and vaccines

Biomedical Journal, Journal Year: 2022, Volume and Issue: 45(4), P. 573 - 579

Published: May 6, 2022

Despite the rising natural and vaccines mediated immunity, several countries have experienced a resurgence of Coronavirus disease 2019 (COVID-19) due to emergence severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. From Alpha Omicron, variants concern (VOC) evolved spike protein mutations that may an impact on virus characteristics, such as transmissibility antigenicity. In this review, we describe evolution SARS-CoV-2, summarize current knowledge epidemiological clinical features variants, discuss response strategies in terms reduce burden COVID-19.

Language: Английский

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Omicron-specific mRNA vaccination alone and as a heterologous booster against SARS-CoV-2

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: June 6, 2022

Abstract The Omicron variant of SARS-CoV-2 recently swept the globe and showed high level immune evasion. Here, we generate an Omicron-specific lipid nanoparticle (LNP) mRNA vaccine candidate, test its activity in animals, both alone as a heterologous booster to WT vaccine. Our LNP-mRNA elicits strong antibody response vaccination-naïve mice. Mice that received two-dose show > 40-fold reduction neutralization potency against than two weeks post boost, which further reduce background after 3 months. or increases waning vaccinated mice by 40 fold at injection. Interestingly, neutralizing titers 10-20 higher homologous variant, with comparable Delta variant. All three types vaccination, including alone, booster, elicit broad binding responses WA-1, Beta, variants SARS-CoV. These data provide direct assessments vaccination vivo,

Language: Английский

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COVID-19 due to the B.1.617.2 (Delta) variant compared to B.1.1.7 (Alpha) variant of SARS-CoV-2: a prospective observational cohort study

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: June 28, 2022

The Delta (B.1.617.2) variant was the predominant UK circulating SARS-CoV-2 strain between May and December 2021. How infection compares with previous variants is unknown. This prospective observational cohort study assessed symptomatic adults participating in app-based COVID Symptom Study who tested positive for from 26 to July 1, 2021 (Delta overwhelmingly variant), compared (1:1, age- sex-matched) individuals presenting 28, 2020 6, (Alpha (B.1.1.7) variant). We illness (symptoms, duration, presentation hospital) during Alpha- Delta-predominant timeframes; transmission, reinfection, vaccine effectiveness period. 3581 (aged 18 100 years) each timeframe were assessed. seven most frequent symptoms common both variants. Within first 28 days of illness, some more versus Alpha (including fever, sore throat, headache) vice versa (dyspnoea). burden week higher infection; however, odds any given symptom lasting ≥ 7 either lower or unchanged. Illness duration infection, though unchanged unvaccinated individuals. Hospitalisation COVID-19 appeared (1.49) transmissible than Alpha. Re-infections low all regions. Vaccination markedly reduced risk (by 69-84%). conclude that infections similar. Alpha; current vaccines showed good efficacy against disease. research framework can be useful future comparisons new emerging

Language: Английский

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