The hyper-transmissible SARS-CoV-2 Omicron variant exhibits significant antigenic change, vaccine escape and a switch in cell entry mechanism

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Jan. 3, 2022

Abstract Vaccines based on the spike protein of SARS-CoV-2 are a cornerstone public health response to COVID-19. The emergence hypermutated, increasingly transmissible variants concern (VOCs) threaten this strategy. Omicron, fifth VOC be described, harbours 30 amino acid mutations in including 15 receptor-binding domain. Here, we demonstrate substantial evasion neutralisation by Omicron vitro using sera from vaccinated individuals. Importantly, these data mirrored reduction real-world vaccine effectiveness that is partially restored booster vaccination. We also does not induce cell syncytia and favours TMPRSS2-independent endosomal entry pathway. Such marked changes antigenicity replicative biology may underlie rapid global spread altered pathogenicity variant.

Language: Английский

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Vaccine effectiveness against SARS-CoV-2 infection or COVID-19 hospitalization with the Alpha, Delta, or Omicron SARS-CoV-2 variant: A nationwide Danish cohort study

PLoS Medicine, Journal Year: 2022, Volume and Issue: 19(9), P. e1003992 - e1003992

Published: Sept. 1, 2022

The continued occurrence of more contagious Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants and waning immunity over time require ongoing reevaluation the vaccine effectiveness (VE). This study aimed to estimate in age groups (12 59 60 years or above) 3 doses (BNT162b2 mRNA mRNA-1273) by since vaccination against SARS-CoV-2 infection Disease 2019 (COVID-19) hospitalization an Alpha-, Delta-, Omicron-dominated period.A Danish nationwide cohort design was used VE COVID-19 with Alpha, Delta, Omicron variant. Information obtained from registries linked using a unique personal identification number. included all previously uninfected residents Denmark aged 12 above (18 for analysis doses) Alpha (February 20 June 15, 2021), Delta (July 4 November 20, (December 21, 2021 January 31, 2022) dominated periods. estimates including 95% confidence intervals (CIs) were calculated (1-hazard ratio∙100) Cox proportional hazard regression models underlying calendar adjustments age, sex, comorbidity, geographical region. Vaccination status as time-varying exposure. In oldest group, after 90.7% (95% CI: 88.2; 92.7) variant, 82.3% 75.5; 87.2) 39.9% 26.3; 50.9) variant 14 30 days vaccination. waned 73.2% (Alpha, 57.1; 83.3), 50.0% (Delta, 46.7; 53.0), 4.4% (Omicron, -0.1; 8.7) >120 Higher observed third dose 86.1% 83.3; 88.4) 57.7% 55.9; 59.5) Among both groups, 98.1% variants. 95.5% main limitation this is nonrandomized potential differences between unvaccinated (reference group) vaccinated individuals.Two provided high protection protection, notably infection, time. Two only limited short-lived Omicron. However, following higher. substantially increased level duration sustained among +60-year-olds.

Language: Английский

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Effectiveness of mRNA vaccines and waning of protection against SARS-CoV-2 infection and severe covid-19 during predominant circulation of the delta variant in Italy: retrospective cohort study

BMJ, Journal Year: 2022, Volume and Issue: unknown, P. e069052 - e069052

Published: Feb. 10, 2022

To estimate the effectiveness of mRNA vaccines against SARS-CoV-2 infection and severe covid-19 at different time after vaccination.

Language: Английский

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Comparative vaccine effectiveness against severe COVID-19 over time in US hospital administrative data: a case-control study

The Lancet Respiratory Medicine, Journal Year: 2022, Volume and Issue: 10(6), P. 557 - 565

Published: Feb. 25, 2022

Language: Английский

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Efficacy and Effectiveness of SARS-CoV-2 Vaccines: A Systematic Review and Meta-Analysis

Vaccines, Journal Year: 2022, Volume and Issue: 10(3), P. 350 - 350

Published: Feb. 23, 2022

The coronavirus disease 2019 (COVID-19) pandemic has threatened global health and prompted the need for mass vaccination. We aimed to assess efficacy effectiveness of COVID-19 vaccines prevent mortality reduce risk developing severe after 1st 2nd doses. From conception 28 June 2021, we searched PubMed, Cochrane, EBSCO, Scopus, ProQuest, Web Science, WHO-ICTRP, Google Scholar. included both observational randomized controlled trials. pooled vaccine following vaccination, as well their 95 percent confidence intervals (CI), were estimated using random-effects model. In total, 22 21,567 screened articles eligible quantitative analysis. Mortality 7 14 days full vaccination decreased significantly among vaccinated group compared unvaccinated (OR = 0.10, ([95% CI, 0.04-0.27], I2 54%) 0.46, [95% 0.35-0.61], 0%), respectively. probability having one or two weeks dose 0.29 0.19-0.46], 25%) 0.08 0.03-0.25], 74%), incidence infection any time doses diminished 0.14 0.07-0.4], 100%) 0.179 0.15-0.19], 98%), Also, week significantly, 0.04, CI (0.01-0.2], 100%). After meta-regression, type country main predictors outcome [non-mRNA type, ß 2.99, p 0.0001; UK, -0.75, 0.038; USA, 0.8, 0.02]. This study showed that most have comparable effectiveness, it is purported may help end this pandemic.

Language: Английский

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Association of COVID-19 Vaccinations With Intensive Care Unit Admissions and Outcome of Critically Ill Patients With COVID-19 Pneumonia in Lombardy, Italy

JAMA Network Open, Journal Year: 2022, Volume and Issue: 5(10), P. e2238871 - e2238871

Published: Oct. 27, 2022

Importance Data on the association of COVID-19 vaccination with intensive care unit (ICU) admission and outcomes patients SARS-CoV-2–related pneumonia are scarce. Objective To evaluate whether is associated preventing ICU for to compare baseline characteristics vaccinated unvaccinated admitted an ICU. Design, Setting, Participants This retrospective cohort study regional data sets reports: (1) daily number administered vaccines (2) all consecutive in Lombardy, Italy, from August 1 December 15, 2021 (Delta variant predominant). Vaccinated received either mRNA (BNT162b2 or mRNA-1273) adenoviral vector (ChAdOx1-S Ad26.COV2). Incident rate ratios (IRRs) were computed 1, 2021, January 31, 2022; analyzed 2021. Exposures status (no vaccination, vaccine, vaccine). Main Outcomes Measures The incidence IRR was evaluated, comparing people unvaccinated, adjusted age sex. at investigated. between mortality hospital discharge also studied, adjusting possible confounders. Results Among 10 107 674 inhabitants time this study, median [IQR] 48 [28-64] years 5 154 914 (51.0%) female. Of 7 863 417 individuals who (median age: 53 [33-68] years; 4 010 343 [51.4%] female), 6 251 (79.5%) 550 439 (7.0%) 061 561 (13.5%) a mix 497 875 (57.2%) boosted. Compared people, vaccine within 120 days last dose 0.03 (95% CI, 0.03-0.04; P < .001), whereas after 0.21 0.19-0.24; .001). There 553 during period: 139 (25.1%) 414 (74.9%) unvaccinated. patients, older [IQR]: 72 [66-76] vs 60 [51-69] primarily male (110 [79.1%] 252 [60.9%]; more comorbidities 2 [1-3] 0 [0-1] comorbidities; .001) had higher ratio arterial partial pressure oxygen (Pa o ) fraction inspiratory (FiO 138 [100-180] [90-158] mm Hg; = .007). Factors age, premorbid heart disease, lower Pa /FiO admission, female sex (this factor only mortality). similar patients. Conclusions Relevance In significantly risk pneumonia. not status. These findings suggest substantial reduction developing COVID-19–related severe acute respiratory failure requiring among people.

Language: Английский

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A systematic review of COVID-19 vaccine efficacy and effectiveness against SARS-CoV-2 infection and disease

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2021, Volume and Issue: unknown

Published: Sept. 25, 2021

ABSTRACT Billions of doses COVID-19 vaccines have been administered globally, dramatically reducing SARS-CoV-2 incidence and severity in some settings. Many studies suggest provide a high degree protection against infection disease, but precise estimates vary differ design, outcomes measured, dosing regime, location, circulating virus strains. Here we conduct systematic review through February 2022. We included efficacy data from Phase 3 clinical trials for 15 undergoing WHO Emergency Use Listing evaluation real-world effectiveness 8 with observational meeting inclusion criteria. Vaccine metrics collected include asymptomatic infection, any symptomatic COVID-19, severe including hospitalization death, partial or complete vaccination, variants concern Alpha, Beta, Gamma, Delta, Omicron. additionally the epidemiological principles behind design interpretation vaccine studies, important sources heterogeneity.

Language: Английский

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Humoral and cellular response of COVID‐19 vaccine among solid organ transplant recipients: A systematic review and meta‐analysis

Transplant Infectious Disease, Journal Year: 2022, Volume and Issue: 24(6)

Published: Aug. 4, 2022

We aimed to analyze the humoral and cellular response standard booster (additional doses) COVID-19 vaccination in solid organ transplantation (SOT) risk factors involved for an impaired response.We did a systematic review meta-analysis of studies published up until January 11, 2022, that reported immunogenicity vaccine among SOT. The study is registered with PROSPERO, number CRD42022300547.Of 1527 studies, 112 which 15391 SOT 2844 healthy controls, were included. showed low (effect size [ES]: 0.44 [0.40-0.48]) overall control (log-Odds-ratio [OR]: -4.46 [-8.10 -2.35]). was highest liver (ES: 0.67 [0.61-0.74]) followed by heart 0.45 [0.32-0.59]), kidney 0.40 [0.36-0.45]), kidney-pancreas 0.33 [0.13-0.53]), lung (0.27 [0.17-0.37]). dose 0.43 [0.39-0.47] vs. 0.51 [0.43-0.54]) marginal increase 18% efficacy. prior infection had higher 0.94 [0.92-0.96] ES: [0.39-0.41]; p-value < .01). seroresponse mRNA-12723 mRNA 0.52 (0.40-0.64). Mycophenolic acid (OR: 1.42 [1.21-1.63]) Belatacept 1.89 [1.3-2.49]) nonresponse. parallelly decreased 0.42 [0.32-0.52]) -3.12 [-0.4.12 -2.13]).Overall, develops suboptimal compared general population. Immunosuppression including mycophenolic acid, belatacept, tacrolimus associated response. Booster doses immune response, but further upgradation strategy required.

Language: Английский

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Testing fractional doses of COVID-19 vaccines

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(8)

Published: Feb. 7, 2022

Due to the enormous economic, health, and social costs of COVID-19 pandemic, there are high expected returns investing in parallel multiple approaches accelerating vaccination. We argue investigating scope for lowering dosage some vaccines. While existing evidence is not dispositive, available clinical data on immunogenicity lower doses combined with a correlation between neutralizing antibody response vaccine efficacy suggests that half or even quarter vaccines could generate levels protection, particularly against severe disease death, while potentially expanding supply by 450 million 1.55 billion per month, based projections 2021. An epidemiological model that, if fractional less effective than standard doses, vaccinating more people faster substantially reduce total infections deaths. The further testing alternative much public health economic benefits. However, commercial incentives dosing weak, suggesting may occur without investment. Governments support either experimental observational evaluations dosing, primary booster shots. Discussions researchers government officials countries where scarce strong interest these approaches.

Language: Английский

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Vaccine effectiveness against SARS-CoV-2 infection and COVID-19-related hospitalization with the Alpha, Delta and Omicron SARS-CoV-2 variants: a nationwide Danish cohort study

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: April 20, 2022

Abstract Background The continued occurrence of more contagious SARS-CoV-2 variants and waning immunity over time require ongoing re-evaluation the vaccine effectiveness (VE). This study aimed to estimate in two age groups (12-59 60 years or above) three doses (BNT162b2 mRNA mRNA-1273 vaccine) by since vaccination against infection COVID-19-related hospitalization an Alpha, Delta Omicron dominated period. Methods A Danish nationwide cohort design was used VE with variants. Information obtained from registries linked using a unique personal identification number. included all residents Denmark aged 12 above (18 for analysis doses) Alpha (February 20 June 15, 2021), (July 4 November 20, 2021) (December 21, 2021 January 31, 2022) periods. estimates including 95% confidence intervals (CIs) were calculated Cox proportional hazard regression models adjustments age, sex geographical region. Vaccination status as time-varying exposure. Findings In oldest group, after 91.0% (95% CI: 88.5; 92.9) variant, 82.2% 75.3; 87.1) variant 39.9% 26.4; 50.9) 14-30 days vaccination. waned 71.5% 54.7; 82.8), 49.8% 46.5; 52.8) 4.7% 0.2; 8.9) >120 variants, respectively. Higher observed third dose 86.0% (Delta, 83.3; 88.3) 57.6% (Omicron, 55.8; 59.4) Among both groups, 94.8% whereas among youngest 62.4% 46.3; 73.6) 89.8% 87.9; 91.3), Conclusions Two provided high protection time. only limited variant. substantially increased Omicron.

Language: Английский

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