ArticleOpen forum infectious diseases2021
SARS-CoV-2 Infection Is at Herd Immunity in the Majority Segment of the Population of Qatar.
Article in Open forum infectious diseases, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 53 papers, 1 of them a synthesis that pooled it.
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Who cites it
53 citing papers in PubMed, 1 synthesis or guideline pooled it, 93 citations in OpenAlex.
- Incidence and outcome of SARS-CoV-2 reinfection in the pre-Omicron era: A global systematic review and meta-analysis.Journal of global health · 2023Pooled it
- 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
- Article
- SARS-CoV-2 infection risk by non-healthcare occupations: a systematic review and meta-analysis.Journal of occupational medicine and toxicology (London, England) · 2025Review
- Prevalence of hepatitis C virus infection in Qatar's resident population based on a national screening campaign.Scientific reports · 2025Article
- Protection conferred by SARS-CoV-2 infection across a spectrum of reinfection symptoms and severities.BMJ open respiratory research · 2025Article
- Article
- Longitudinal cellular and humoral immune responses following COVID-19 BNT162b2-mRNA-based booster vaccination of craft and manual workers in Qatar.Frontiers in immunology · 2025Article
- SARS-CoV-2 infection prevalence, risk factors, and outcomes among non-clinical-related service providers in a national healthcare system.Global epidemiology · 2024Article
- Prevalence of syphilis infection among migrant workers in Qatar: a nationwide cross-sectional survey.BMJ open · 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
- Prevalence of hepatitis B and C viruses among migrant workers in Qatar.Scientific reports · 2024Article
- Article
- Addressing bias in the definition of SARS-CoV-2 reinfection: implications for underestimation.Frontiers in medicine · 2024Article
Corrections and comments
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Authors and funding
46 authors at 7 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundQatar experienced a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic that disproportionately affected the craft and manual worker (CMW) population, who comprise 60% of the total population. This study aimed to assess ever and/or current infection prevalence in this population.
methodsA cross-sectional population-based survey was conducted during July 26 to September 09, 2020, to assess both anti-SARS-CoV-2 positivity through serological testing and current infection positivity through polymerase chain reaction (PCR) testing. Associations with antibody and PCR positivity were identified through regression analyses.
resultsThe study included 2641 participants, 69.3% of whom were <40 years of age. Anti-SARS-CoV-2 positivity was 55.3% (95% CI, 53.3%-57.3%) and was significantly associated with nationality, geographic location, educational attainment, occupation, and previous infection diagnosis. PCR positivity was 11.3% (95% CI, 9.9%-12.8%) and was significantly associated with nationality, geographic location, occupation, contact with an infected person, and reporting 2 or more symptoms. Infection positivity (antibody and/or PCR positive) was 60.6% (95% CI, 58.6%-62.5%). The proportion of antibody-positive CMWs who had a prior SARS-CoV-2 diagnosis was 9.3% (95% CI, 7.9%-11.0%). Only seven infections were ever severe, and only 1 was ever critical-an infection severity rate of 0.5% (95% CI, 0.2%-1.0%).
conclusionsSix in every 10 CMWs in Qatar have been infected, suggestive of reaching the herd immunity threshold. Infection severity was low, with only 1 in every 200 infections progressing to be severe or critical. Only 1 in every 10 infections had been previously diagnosed, which is suggestive of mostly asymptomatic or mild infections.
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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.