ArticleEnfermedades infecciosas y microbiologia clinica (English ed.)2024
Comparative severity of COVID-19 cases caused by Alpha, Delta or Omicron SARS-CoV-2 variants and its association with vaccination.
Article in Enfermedades infecciosas y microbiologia clinica (English ed.), 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers, 2 of them syntheses that pooled it.
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Who cites it
19 citing papers in PubMed, 2 syntheses or guidelines pooled it, 16 citations in OpenAlex.
- Neutralising antibodies and protection from progression to severe COVID-19: A meta-analysis.PLoS medicine · 2026Pooled it
- Individual risk factors associated with SARS-CoV-2 infection during Alpha variant in high-income countries: a systematic review and meta-analysis.Frontiers in public health · 2024Pooled it
- COVID-19 outcomes among vaccinated and unvaccinated patients receiving disease-modifying antirheumatic drugs and biologic therapies: a retrospective multihospital cohort study.Clinical rheumatology · 2026Article
- Severe Vision Impairment and Its Association with COVID-19 Susceptibility, Severity, and Mortality: A Population-Based Cohort Study.Journal of clinical medicine · 2026Article
- Estimating the effect of self-protection on transmission dynamics of SARS-CoV-2 in Germany in 2021: a modelling study.BMC public health · 2026Article
- Article
- Genomic surveillance of SARS-CoV-2 variants in hospitalized patients: a cohort study from the metropolitan area of valle de Aburrá, ColombiaBiomedica : revista del Instituto Nacional de Salud · 2026Article
- Pathomorphological Features of Lung Damage Caused by Infection with Various Variants of SARS-CoV-2 in Humanized Model Animals.Doklady. Biochemistry and biophysics · 2026Article
- Neurocognitive and Psychiatric Outcomes Following Mild to Moderate COVID-19: A Longitudinal Comparison of Alpha/Delta and Omicron Variants.Neuropsychiatric disease and treatment · 2026Article
- COVIDmeter - a questionnaire-based symptom monitoring system for the surveillance of COVID-19 in Denmark, 2020-2023.Epidemiology and infection · 2025Article
- Impact of COVID-19 Vaccination on Hospitalization and Mortality: A Comparative Analysis of Clinical Outcomes During the Early Phase of the Pandemic.Infectious disease reports · 2025Article
- Sex Differences in Long-Term Cardiovascular Outcomes and Mortality After COVID-19 Hospitalization During Alpha, Delta and Omicron Waves.Journal of clinical medicine · 2024Article
- Genital Dysbiosis and Different Systemic Immune Responses Based on the Trimester of Pregnancy in SARS-CoV-2 Infection.International journal of molecular sciences · 2024Article
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- Article
- Analyzing the worldwide progression of COVID-19 cases and deaths using nonlinear mixed-effects model.PloS one · 2024Article
- Safety and Effectiveness of Regdanvimab for COVID-19 Treatment: A Phase 4 Post-marketing Surveillance Study Conducted in South Korea.Infectious diseases and therapy · 2023Article
- Article
- Effects of Different Types of Recombinant SARS-CoV-2 Spike Protein on Circulating Monocytes' Structure.International journal of molecular sciences · 2023Article
Corrections and comments
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Authors and funding
13 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThis study compares the severity of SARS-CoV-2 infections caused by Alpha, Delta or Omicron variants in periods of co-circulation in Spain, and estimates the variant-specific association of vaccination with severe disease.
methodsSARS-CoV-2 infections notified to the national epidemiological surveillance network with information on genetic variant and vaccination status were considered cases if they required hospitalisation or controls otherwise. Alpha and Delta were compared during June-July 2021; and Delta and Omicron during December 2021-January 2022. Adjusted odds ratios (aOR) were estimated using logistic regression, comparing variant and vaccination status between cases and controls.
resultsWe included 5,345 Alpha and 11,974 Delta infections in June-July and 5,272 Delta and 10,578 Omicron in December-January. Unvaccinated cases of Alpha (aOR: 0.57; 95% CI: 0.46-0.69) or Omicron (0.28; 0.21-0.36) had lower probability of hospitalisation vs. Delta. Complete vaccination reduced hospitalisation, similarly for Alpha (0.16; 0.13-0.21) and Delta (June-July: 0.16; 0.14-0.19; December-January: 0.36; 0.30-0.44) but lower from Omicron (0.63; 0.53-0.75) and individuals aged 65+ years.
conclusionResults indicate higher intrinsic severity of the Delta variant, compared with Alpha or Omicron, with smaller differences among vaccinated individuals. Nevertheless, vaccination was associated to reduced hospitalisation in all groups.
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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.