ArticleiScience2021
SARS-CoV-2 seroprevalence in the urban population of Qatar: An analysis of antibody testing on a sample of 112,941 individuals.
Article in iScience, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 54 papers.
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Who cites it
54 citing papers in PubMed, 99 citations in OpenAlex.
- Two Versus One COVID-19 Vaccine Dose After Prior SARS-CoV-2 Infection: A Nationwide Retrospective Cohort Study.Open forum infectious diseases · 2026Article
- Evaluating COVID-19 vaccine effectiveness across epidemiologic designs: test-negative case-control versus retrospective cohort analyses in a nationwide study.International journal of epidemiology · 2026Article
- Global Estimates of COVID-19 Morbidity and Mortality: A Cohort Study and Mathematical Model Analysis.Influenza and other respiratory viruses · 2025Article
- Effectiveness and durability of a fourth dose of ancestral-strain mRNA vaccines against SARS-CoV-2 infection: a nationwide matched cohort study in Qatar.Scientific reports · 2025Article
- Effectiveness of ChAdOx1 nCoV-19 (Vaxzevria) primary series vaccine against SARS-CoV-2 beta and delta variants: a nationwide study.BMC infectious diseases · 2025Article
- Immune histories and natural infection protection during the omicron era.Communications medicine · 2025Article
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- Protection conferred by SARS-CoV-2 infection across a spectrum of reinfection symptoms and severities.BMJ open respiratory research · 2025Article
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- SARS-CoV-2 infection prevalence, risk factors, and outcomes among non-clinical-related service providers in a national healthcare system.Global epidemiology · 2024Article
- BNT162b2 Versus mRNA-1273 Vaccines: Comparative Analysis of Long-Term Protection Against SARS-CoV-2 Infection and Severe COVID-19 in Qatar.Influenza and other respiratory viruses · 2024Article
- Estimating protection afforded by prior infection in preventing reinfection: applying the test-negative study design.American journal of epidemiology · 2024Article
- Pilot study in Hamburg on the prevalence of SARS-CoV-2 infections and pandemic survey in the German funeral industry.Forensic science, medicine, and pathology · 2024Article
- Article
- Addressing bias in the definition of SARS-CoV-2 reinfection: implications for underestimation.Frontiers in medicine · 2024Article
- SARS-CoV-2 infection and effects of age, sex, comorbidity, and vaccination among older individuals: A national cohort study.Influenza and other respiratory viruses · 2023Article
- History of primary-series and booster vaccination and protection against Omicron reinfection.Science advances · 2023Article
- Pfizer-BioNTech mRNA Vaccine Protection among Children and Adolescents Aged 12-17 Years against COVID-19 Infection in Qatar.Vaccines · 2023Article
- Effects of previous infection, vaccination, and hybrid immunity against symptomatic Alpha, Beta, and Delta SARS-CoV-2 infections: an observational study.EBioMedicine · 2023Observational
- Seroprevalence of COVID-19 in Oran: Cross-Sectional Study.Microbiology spectrum · 2023Article
Corrections and comments
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Authors and funding
24 authors at 7 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The study objective was to the assess level of detectable severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in the urban population of Qatar. Antibody testing was performed on residual blood specimens for 112,941 individuals (∼10% of Qatar's urban population) attending for routine/other clinical care between May 12 and September 9, 2020. Seropositivity was 13.3% (95% confidence interval [CI] = 13.1-13.6%) and was independently associated with sex, age, nationality, clinical care encounter type, and testing date. Median optical density (antibody titer) among antibody-positive persons was 27.0 (range = 1.0-150.0), with higher values associated with age, nationality, clinical care encounter type, and testing date. Seropositivity by nationality was positively correlated with the likelihood of having higher antibody titers (Pearson correlation coefficient = 0.85; 95% CI = 0.47-0.96). Less than two in every 10 individuals in Qatar's urban population had detectable antibodies against SARS-CoV-2, suggesting this population is still far from herd immunity and at risk of subsequent infection waves. Higher antibody titer appears to be a biomarker of repeated exposures to the infection.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.