ArticleLancet regional health. Americas2021
Vaccination reduces need for emergency care in breakthrough COVID-19 infections: A multicenter cohort study.
Article in Lancet regional health. Americas, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 72 papers, 4 of them syntheses that pooled it.
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Who cites it
72 citing papers in PubMed, 4 syntheses or guidelines pooled it, 119 citations in OpenAlex.
- Knowledge Gaps for Prophylactic Use of Antithrombotic Agents in Patients with COVID-19: Insights into New SARS-CoV-2 Variants, Vaccination Status, and Emerging Oral Antivirals.Thrombosis and haemostasis · 2023Pooled it
- Clinical manifestations of COVID-19 breakthrough infections: A systematic review and meta-analysis.Journal of medical virology · 2022Pooled it
- Sufficient Sleep, Time of Vaccination, and Vaccine Efficacy: A Systematic Review of the Current Evidence and a Proposal for COVID-19 Vaccination.The Yale journal of biology and medicine · 2022Pooled it
- Epidemiological and clinical characteristics of vaccinated COVID-19 patients: A meta-analysis and systematic review.International journal of immunopathology and pharmacologyPooled it
- Patient Safety Implications of Opportunistic Pathogens and Healthcare-Associated Infections in COVID-19 Patients: A Narrative Review.Healthcare (Basel, Switzerland) · 2026Review
- COVID-19 vaccine hesitancy among Latinx individuals in North Texas: Understandings from a community study.Human vaccines & immunotherapeutics · 2025Article
- Long-Term Durability and Variant-Specific Modulation of SARS-CoV-2 Humoral and Cellular Immunity over Two Years.International journal of molecular sciences · 2025Article
- Functional antibody responses to SARS-CoV-2 variants before and after booster vaccination among adults in Ghana.Experimental biology and medicine (Maywood, N.J.) · 2025Article
- Impact of vaccination and SARS-CoV-2 variants on severe COVID-19 outcomes: a cross-sectional study, Brazil, 2021-2022.Epidemiologia e servicos de saude : revista do Sistema Unico de Saude do Brasil · 2025Article
- Rationing, Responsibility, and Vaccination during COVID-19: A Conceptual Map.The American journal of bioethics : AJOB · 2024Article
- Article
- Cardioprotective effects of vaccination in hospitalized patients with COVID-19.Clinical and experimental medicine · 2024Article
- Development and evaluation of a Lateral flow immunoassay (LFIA) prototype for the detection of IgG anti-SARS-CoV-2 antibodies.Heliyon · 2024Article
- The Role of Coinhibitory Receptors in B Cell Dysregulation in SARS-CoV-2-Infected Individuals with Severe Disease.Journal of immunology (Baltimore, Md. : 1950) · 2024Article
- External Validation of Prognostic Models in Critical Care: A Cautionary Tale From COVID-19 Pneumonitis.Critical care explorations · 2024Article
- Vaccines reduced hospital length of stay and fraction of inspired oxygen of COVID-19 patients: A retrospective cohort study.Preventive medicine reports · 2024Article
- Impact of vaccination status on clinical outcomes of hospitalized COVID-19 patients.BMC infectious diseases · 2024Article
- Association between ABO blood type and coronavirus disease 2019 severe outcomes across dominant variant strains.Journal of the American College of Emergency Physicians open · 2024Article
- Vaccination protects against acute respiratory distress syndrome (ARDS) in hospitalized patients with COVID-19.Clinical and experimental medicine · 2024Article
- Editorial: The adaptive value of languages: non-linguistic causes of language diversity, volume II.Frontiers in psychology · 2024Article
12 more citing papers are in PubMed but not listed here.
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Authors and funding
7 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundWhile recent literature has shown the efficacy of the SARS-CoV-2 vaccine in preventing infection, it's impact on need for emergency care/hospitalization in breakthrough infections remain unclear, particularly in regions with a high rate of variant viral strains. We aimed to determine if vaccination reduces hospital visits in breakthrough COVID-19.
methodsThis observational cohort analysis compared unvaccinated (UV), partially vaccinated (PV), and fully vaccinated (FV) adult patients with SARS-CoV-2 infection requiring emergency care(EC)/hospitalization within an eight-hospital system in Michigan. Demographic and clinical variables were obtained from the electronic record. Vaccination data was obtained from the Michigan Care Improvement Registry and Centers for Disease Control vaccine tracker. Primary endpoint was rate of emergency care/hospitalization encounters among patients diagnosed with COVID-19. Secondary outcome was severe disease-composite outcome (ICU, mechanical ventilation, or in-hospital death).
findingsBetween December 15,2020 and April 30,2021, 11,834 EC encounters were included:10,880 (91.9%) UV, 825 (7%) PV, 129 (1.1%) FV. Average age was 53.0 ± 18.2 and 52.8% were female. Accounting for the SARS-CoV-2 vaccination population groups in Michigan, the ED encounters/hospitalizations rate relevant to COVID-19 was 96% lower in FV versus UV (multiplicative effect:0.04, 95% CI 0.03 to 0.06, p < 0.001) in negative binomial regression. COVID-19 EC visits rate peaked at 22.61, 12.88, and 1.29 visits per 100000 for the UV, PV, and FV groups, respectively. In the propensity-score matching weights analysis, FV had a lower risk of composite disease compared to UV but statistically insignificant (HR 0.84, 95% CI 0.52 to 1.38).
interpretationThe need for emergency care/hospitalization due to breakthrough COVID-19 is an exceedingly rare event in fully vaccinated patients. As vaccination has increased regionally, EC visits amongst fully vaccinated individuals have remained low and occur much less frequently than unvaccinated individuals. If hospital-based treatment is required, elderly patients with significant comorbidities are at high-risk for severe outcomes regardless of vaccination status.
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