SARS-CoV-2 reinfections: Overview of efficacy and duration of natural and hybrid immunity

Environmental Research, Journal Year: 2022, Volume and Issue: 209, P. 112911 - 112911

Published: Feb. 8, 2022

Seroprevalence surveys suggest that more than a third and possibly half of the global population has been infected with SARS-CoV-2 by early 2022. As large numbers people continue to be infected, efficacy duration natural immunity in terms protection against reinfections severe disease is crucial significance for future. This narrative review provides an overview on epidemiological studies addressing this issue. National covering 2020-2021 documented previous infection associated significantly reduced risk lasting at least one year only relatively moderate waning immunity. Importantly, showed roughly similar effect sizes regarding reinfection across different variants, exception Omicron variant which data are just emerging before final conclusions can drawn. Risk hospitalizations deaths was also versus primary infections. Observational indicate may offer equal or greater infections compared individuals receiving two doses mRNA vaccine, but not fully consistent. The combination respective vaccination, termed hybrid immunity, seems confer greatest infections, several knowledge gaps remain Natural should considered public health policy SARS-CoV-2.

Language: Английский

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Immunological memory to SARS‐CoV ‐2 infection and COVID ‐19 vaccines

Immunological Reviews, Journal Year: 2022, Volume and Issue: 310(1), P. 27 - 46

Published: June 22, 2022

Immunological memory is the basis of protective immunity provided by vaccines and previous infections. can develop from multiple branches adaptive immune system, including CD4 T cells, CD8 B long-lasting antibody responses. Extraordinary progress has been made in understanding to SARS-CoV-2 infection COVID-19 vaccines, addressing development; quantitative qualitative features different cellular anatomical compartments; durability each component antibodies. Given sophistication measurements; size human studies; use longitudinal samples cross-sectional head-to-head comparisons between or for 1 year already supersedes that any other acute infectious disease. This knowledge may help inform public policies regarding as well scientific development future against diseases.

Language: Английский

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T Cell Responses to SARS-CoV-2

Annual Review of Immunology, Journal Year: 2023, Volume and Issue: 41(1), P. 343 - 373

Published: Feb. 8, 2023

A large body of evidence generated in the last two and a half years addresses roles T cells SARS-CoV-2 infection following vaccination. Infection or vaccination induces multi-epitope CD4 CD8 cell responses with polyfunctionality. Early have been associated mild COVID-19 outcomes. In concert animal model data, these results suggest that while antibody are key to prevent infection, may also play valuable reducing disease severity controlling infection. memory after is sustained for at least six months. While neutralizing impacted by variants, most preserved. This review highlights extensive progress made, data knowledge gaps remain, our understanding vaccines.

Language: Английский

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Percentage of Asymptomatic Infections among SARS-CoV-2 Omicron Variant-Positive Individuals: A Systematic Review and Meta-Analysis

Vaccines, Journal Year: 2022, Volume and Issue: 10(7), P. 1049 - 1049

Published: June 30, 2022

Background: Asymptomatic infections are potential sources of transmission for coronavirus disease 2019, especially during the epidemic SARS-CoV-2 Omicron variant. We aimed to assess percentage asymptomatic among variant-positive individuals detected by gene sequencing or specific polymerase chain reaction (PCR). Methods: searched PubMed, EMBASE, and Web Science from 26 November 2021 13 April 2022. This meta-analysis was conducted following Preferred Reporting Items Systematic Reviews Meta-Analyses guidelines registered with PROSPERO (CRD42022327894). Three researchers independently extracted data two assessed quality using pre-specified criteria. The pooled 95% confidence interval (CI) estimated random-effects models. Results: Our included eight eligible studies, covering 7640 2190 infections. 32.40% (95% CI: 25.30−39.51%) individuals, which higher in population developing countries (38.93%; 19.75−58.11%), vaccine coverage ≥ 80% (35.93%; 25.36−46.51%), a travel history (40.05%; 7.59−72.51%), community infection (37.97%; 10.07−65.87%), median age < 20 years (43.75%; 38.45−49.05%). Conclusion: In this systematic review meta-analysis, individuals. people who were vaccinated, young (median years), had history, infected outside clinical setting (community infection) percentages Screening is required prevent clustered epidemics sustained caused variants, regions that have successfully controlled SARS-CoV-2.

Language: Английский

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The COVID-19 pandemic in the African continent

BMC Medicine, Journal Year: 2022, Volume and Issue: 20(1)

Published: May 2, 2022

In December 2019, a new coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and associated disease, coronavirus disease 2019 (COVID-19), was identified in China. This virus spread quickly March, 2020, it declared pandemic. Scientists predicted the worst scenario to occur Africa since least developed of continents terms human development index, lagged behind others achievement United Nations sustainable goals (SDGs), has inadequate resources for provision social services, many fragile states. addition, there were relatively few research reporting findings on COVID-19 Africa. On contrary, more countries reported higher incidences mortality rates. However, Africa, earlier predictions modelling into incidence did not fit reality. Therefore, main objective this forum is bring together infectious diseases public health experts give an overview share their thoughts opinions why behaved way did. Furthermore, highlight what needs be done support consolidate status quo overcome negative effects so as accelerate attainment SDGs.

Language: Английский

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Global SARS-CoV-2 genomic surveillance: What we have learned (so far)

Infection Genetics and Evolution, Journal Year: 2023, Volume and Issue: 108, P. 105405 - 105405

Published: Jan. 18, 2023

The COVID-19 pandemic has brought significant challenges for genomic surveillance strategies in public health systems worldwide. During the past thirty-four months, many countries faced several epidemic waves of SARS-CoV-2 infections, driven mainly by emergence and spread novel variants. In that line, been a crucial toolkit to study real-time evolution, assessment optimization diagnostic assays, improve efficacy existing vaccines. pandemic, identification emerging lineages carrying lineage-specific mutations (particularly those Receptor Binding domain) showed how these might significantly impact viral transmissibility, protection from reinfection vaccination. So far, an unprecedented number genomes released databases (i.e., GISAID, NCBI), achieving 14 million genome sequences available as early-November 2022. present review, we summarise global landscape during first months circulation evolution. It demonstrates urgency importance sustained investment timely identify any potential pathogen or associated variants, which turn is key preparedness.

Language: Английский

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Rapid synchronous type 1 IFN and virus-specific T cell responses characterize first wave non-severe SARS-CoV-2 infections

Cell Reports Medicine, Journal Year: 2022, Volume and Issue: 3(3), P. 100557 - 100557

Published: March 1, 2022

Effective control of SARS-CoV-2 infection on primary exposure may reveal correlates protective immunity to future variants, but we lack insights into immune responses before or at the time virus is first detected. We use blood transcriptomics, multiparameter flow cytometry, and T cell receptor (TCR) sequencing spanning incident non-severe in unvaccinated virus-naive individuals identify rapid type 1 interferon (IFN) common other acute respiratory viruses proliferation that discriminate from viruses. These peak by detected sometimes precede detection. Cell most evident CD8 cells associated with specific expansion SARS-CoV-2-reactive TCRs, contrast virus-specific antibodies, which lag 1-2 weeks. Our data support a role for early IFN responses, implications development universal vaccines.

Language: Английский

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SARS-CoV-2 infection and vaccination trigger long-lived B and CD4+ T lymphocytes with implications for booster strategies

Journal of Clinical Investigation, Journal Year: 2022, Volume and Issue: 132(6)

Published: Feb. 9, 2022

BACKGROUNDImmunization against SARS-CoV-2, the causative agent of COVID-19, occurs via natural infection or vaccination. However, it is currently unknown how long infection- vaccination-induced immunological memory will last.METHODSWe performed a longitudinal evaluation to SARS-CoV-2 up 1 year after and following mRNA vaccination in naive individuals recovered from COVID-19 infection.RESULTSWe found that cells are still detectable 8 months vaccination, while antibody levels decline significantly, especially individuals. We also booster injection efficacious reactivating spike protein individuals, whereas was ineffective previously SARS-CoV-2-infected Finally, we observed similar kinetics decay humoral cellular immunity cohort unvaccinated individuals.CONCLUSIONShort-term persistence immunity, together with reduced neutralization capacity versus prevailing variants, may account for reinfections breakthrough infections. Long-lived B CD4+ T protect severe disease development. In dose restored optimal anti-spike needs vaccinated who have yet be defined.FUNDINGThis study supported by funds Department Experimental Clinical Medicine, University Florence (Project Excellence Departments 2018-2022), (project RICTD2122), Italian Ministry Health (COVID-2020-12371849), region Tuscany (TagSARS CoV 2).

Language: Английский

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SARS-CoV-2 nonstructural protein 6 triggers endoplasmic reticulum stress-induced autophagy to degrade STING1

Autophagy, Journal Year: 2023, Volume and Issue: 19(12), P. 3113 - 3131

Published: July 23, 2023

aa: amino acid; ATF6: activating transcription factor 6; ATG5: autophagy related 5; CCPG1: cell cycle progression 1; CFTR: CF transmembrane conductance regulator; cGAMP: cyclic GMP-AMP; CGAS: GMP-AMP synthase; CHX: cycloheximide; Co-IP: co-immunoprecipitation; CQ: chloroquine; EIF2A/eIF2α: eukaryotic translation initiation 2A; EIF2AK3/PERK: 2 alpha kinase 3; ER: endoplasmic reticulum; ERN1/IRE1: reticulum to nucleus signaling GFP: green fluorescent protein; HSPA5/GRP78: heat shock protein family A (Hsp70) member HSV-1: herpes simplex virus type IFIT1: interferon induced with tetratricopeptide repeats IFNB1/IFN-β: beta IRF3: regulatory ISG15: ISG15 ubiquitin like modifier; MAP1LC3B/LC3B: microtubule associated 1 light chain 3 beta; MAP3K7/TAK1: mitogen-activated 7; MAVS: mitochondrial antiviral MOI: multiplicity of infection; NFKB/NF-κB: nuclear kappa B; NSP6: non-structural Δ106-108: deletion acids 106-108 in NSP6 SARS-CoV-2; Δ105-107: 105-107 RETREG1/FAM134B: reticulophagy regulator RIGI/DDX58: RNA sensor RIG-I; SQSTM1/p62: sequestosome STING1: stimulator response cGAMP interactor TBK1: TANK binding 1.

Language: Английский

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Smart and emerging point of care electrochemical sensors based on nanomaterials for SARS-CoV-2 virus detection: Towards designing a future rapid diagnostic tool

Chemosphere, Journal Year: 2024, Volume and Issue: 352, P. 141269 - 141269

Published: Jan. 31, 2024

Language: Английский

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