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Diagnostic Efficiency of Three Fully Automated Serology Assays and Their Correlation with a Novel Surrogate Virus Neutralization Test in Symptomatic and Asymptomatic SARS-COV-2 Individuals
(
MDPI
, 2020 , Article)
Abstract: To support the deployment of serology assays for population screening during the
COVID-19 pandemic, we compared the performance of three fully automated SARS-CoV-2 IgG assays: Mindray CL-900i® (target: spike [S] ...
Effectiveness of two and three doses of COVID-19 mRNA vaccines against infection, symptoms, and severity in the pre-omicron era: A time-dependent gradient
(
Elsevier
, 2024 , Article)
BackgroundVaccines were developed and deployed to combat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aimed to characterize patterns in the protection provided by the BNT162b2 and ...
Effects of SARS-CoV-2 Alpha, Beta, and Delta variants, age, vaccination, and prior infection on infectiousness of SARS-CoV-2 infections
(
Frontiers Media
, 2022 , Article)
In 2021, Qatar experienced considerable incidence of SARS-CoV-2 infection that was dominated sequentially by the Alpha, Beta, and Delta variants. Using the cycle threshold (Ct) value of an RT-qPCR-positive test to proxy ...
Population immunity of natural infection, primary-series vaccination, and booster vaccination in Qatar during the COVID-19 pandemic: an observational study
(
Elsevier
, 2023 , Article)
BackgroundWaning of natural infection protection and vaccine protection highlight the need to evaluate changes in population immunity over time. Population immunity of previous SARS-CoV-2 infection or of COVID-19 vaccination ...
Effects of previous infection, vaccination, and hybrid immunity against symptomatic Alpha, Beta, and Delta SARS-CoV-2 infections: an observational study
(
Elsevier
, 2023 , Article)
BackgroundProtection against SARS-CoV-2 symptomatic infection and severe COVID-19 of previous infection, mRNA two-dose vaccination, mRNA three-dose vaccination, and hybrid immunity of previous infection and vaccination ...
Short- and longer-term all-cause mortality among SARS-CoV-2- infected individuals and the pull-forward phenomenon in Qatar: a national cohort study
(
Elsevier
, 2023 , Article)
ObjectivesWe assessed short-, medium-, and long-term all-cause mortality risks after a primary SARS-CoV-2 infection. MethodsA national, matched, retrospective cohort study was conducted in Qatar to assess risk of all-cause ...
Addressing bias in the definition of SARS-CoV-2 reinfection: implications for underestimation
(
Frontiers Media
, 2024 , Article)
Introduction: Reinfections are increasingly becoming a feature in the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, accurately defining reinfection poses methodological ...
Follow up and comparative assessment of IgG, IgA, and neutralizing antibody responses to SARS-CoV-2 between mRNA-vaccinated naïve and unvaccinated naturally infected individuals over 10 months
(
Elsevier
, 2023 , Article)
BackgroundEvidence on the effectiveness of vaccination-induced immunity compared to SARS-CoV-2 natural immunity is warranted to inform vaccination recommendations. AimIn this study, we aimed to conduct a comparative ...
SARS-CoV-2 infection and effects of age, sex, comorbidity, and vaccination among older individuals: A national cohort study
(
Wiley
, 2023 , Article)
Background: We investigated the contribution of age, coexisting medical conditions, sex, and vaccination to incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and of severe, critical, or ...
Protection of natural infection against reinfection with SARS-CoV-2 JN.1 variant
(
Oxford University Press
, 2024 , Article)
Evidence at the level of neutralizing antibodies suggests that the SARS-CoV-2 JN.1 variant demonstrates increased immune evasion compared to its parent lineage BA.2.86 and to recently circulating variants, such as XBB.1.5 ...