ArticleEpidemiologia (Basel, Switzerland)2023
ABO Blood Groups and Incidence of COVID-19 in the Mass Gathering Events in Borriana (Spain), March 2020: A Retrospective Cohort Study.
Article in Epidemiologia (Basel, Switzerland), 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
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Who cites it
9 citing papers in PubMed.
- Nationwide Distribution of ABO and Rh Blood Group Phenotypes Among Mexican Outpatients: A Multicenter Retrospective Cross-Sectional Study.Journal of blood medicine · 2026Article
- Seroepidemiology of Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Blood Donors from Western Romania, August-September 2023.Microorganisms · 2025Article
- Vitamin D Status and Incidence of SARS-CoV-2 Reinfections in the Borriana COVID-19 Cohort: A Population-Based Prospective Cohort Study.Tropical medicine and infectious disease · 2025Article
- The Investigation of the Distribution of ABO/Rh Blood Group in Hospitalized COVID-19 Patients and Its Association With Disease Severity, Clinical Outcomes, Lab Tests, and Radiologic Findings.Health science reports · 2025Article
- Cellular Immunity of SARS-CoV-2 in the Borriana COVID-19 Cohort: A Nested Case-Control Study.Epidemiologia (Basel, Switzerland) · 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
- Article
- Incidence and Risk Factors of the COVID-19 Pandemic: An Epidemiological Approach.Epidemiologia (Basel, Switzerland) · 2023Article
- Association of ABO blood types and clinical variables with COVID-19 infection severity in Libya.SAGE open medicine · 2023Article
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Authors and funding
27 authors.
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Abstract
Our objective was to estimate the incidence of COVID-19 and the ABO blood Groups in the mass-gathering events (MGEs) during the Falles Festival in Borriana (Spain) from 6-10 March 2020. We conducted a population-based retrospective cohort study and measured anti-SARS-CoV-2 antibodies and the ABO of participants. We performed laboratory COVID-19 tests and obtained the ABO in 775 subjects (72.8% of the original exposed cohort): O-group (45.2%), A-group (43.1%), B-group (8.5%) and AB-group (3.4%). Adjusted for confounding factors, including COVID-19 exposure during the MGEs, attack rates of COVID-19 for each ABO group were 55.4%, 59.6%, 60.2%, and 63.7%. The adjusted relative risks were for O-group 0.93 (95% Confidence Interval [CI] 0.83-1.04), for A-group 1.06 (95% CI 0.94-1.18), for B-group 1.04 (95%CI 0.88-1.24), and for AB-group 1.11 (95% CI 0.81-1.51) with no significant differences. Conclusions: Our results suggest no effect of ABO on COVID-19 incidence. We observed weak but not significant protection of the O-group and not a significantly greater infection risk for the remaining groups compared with the O-group. More studies are needed to resolve the controversies regarding the association between ABO and COVID-19.
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