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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] ...
Duration of mRNA vaccine protection against SARS-CoV-2 Omicron BA.1 and BA.2 subvariants in Qatar.
(
Nature Research
, 2022 , Article)
SARS-CoV-2 Omicron BA.1 and BA.2 subvariants are genetically divergent. We conducted a matched, test-negative, case-control study to estimate duration of protection of the second and third/booster doses of mRNA COVID-19 ...
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 ...
Effect of mRNA Vaccine Boosters against SARS-CoV-2 Omicron Infection in Qatar.
(
Massachusetts Medical Society
, 2022 , Article)
Waning of vaccine protection against coronavirus disease 2019 (Covid-19) and the emergence of the omicron (or B.1.1.529) variant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have led to expedited ...
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 ...
Covid-19 Vaccine Protection among Children and Adolescents in Qatar.
(
Massachusetts Medical Society
, 2022 , Article)
The BNT162b2 vaccine against coronavirus disease 2019 (Covid-19) has been authorized for use in children 5 to 11 years of age and adolescents 12 to 17 years of age but in different antigen doses. We assessed the real-world ...
Bivalent mRNA-1273.214 vaccine effectiveness against SARS-CoV-2 omicron XBB* infections
(2023 , Article)
In October of 2022, Qatar introduced COVID-19 bivalent vaccination for persons ≥ 12 years using the 50-μg mRNA-1273.214 vaccine combining SARS-CoV-2 ancestral and omicron BA.1 strains.1 We estimated this vaccine’s effectiveness ...
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 ...