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Published on: June 23, 2022
Design and Implementation of a Nationwide Population-Based Longitudinal Survey of SARS-CoV-2 Infection in Spain: The
Roberto Pastor-Barriuso1, Beatriz Pérez-Gómez1, Jesús Oteo-Iglesias1
1Roberto Pastor-Barriuso, Beatriz Pérez-Gómez, Nerea Fernández-de-Larrea, and Marina Pollán are with the National Centre for Epidemiology and the Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III (ISCIII), Madrid, Spain. Jesús Oteo-Iglesias, Mayte Pérez-Olmeda, and Aurora Fernández-García are with the National Centre for Microbiology and the Consortium for Biomedical Research in Infectious Diseases (CIBERINFEC), ISCIII. Miguel A. Hernán is with the Departments of Epidemiology and Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA. Marta Molina, Mariano Martín, José L. Sanmartín, Juan F. Muñoz-Montalvo, and Faustino Blanco are with the Deputy Directorate of Information Technologies, Ministry of Health, Madrid, Spain. Israel Cruz is with the National School of Public Health, ISCIII. José León-Paniagua and Raquel Yotti are with ISCIII.
Abstract:
Data System. The Spanish National Seroepidemiological Survey of SARS-CoV-2 (or ENE-COVID; SARS-CoV-2 [severe acute respiratory syndrome coronavirus 2] is the causative agent of COVID-19) was funded by the Spanish Ministry of Health, the Instituto de Salud Carlos III, and the Spanish National Health System. Data Collection/Processing. A stratified 2-stage probability sampling was used to select a representative cohort of the noninstitutionalized population of Spain. ENE-COVID collected longitudinal data from epidemiological questionnaires and 2 SARS-CoV-2 IgG antibody tests. From April 27 to June 22, 2020, 68 287 participants (77.0% of contacted persons) received a point-of-care test and 61 095 (68.9%) also underwent a laboratory immunoassay. A second follow-up phase was conducted between November 16 and 30, 2020. Data Analysis/Dissemination. Analyses use weights to adjust for oversampling and nonresponse and account for design effects of stratification and clustering. ENE-COVID data for research purposes will be available upon request from the official study Web page. Public Health Implications. ENE-COVID, a nationwide population-based study, allowed monitoring seroprevalence of antibodies against SARS-CoV-2 at the national and regional levels, providing accurate figures by gender, age (from babies to nonagenarians), and selected risk factors; characterizing symptomatic and asymptomatic infections; and estimating the infection fatality risk during the first pandemic wave. (Am J Public Health. 2023;113(5):525-532. https://doi.org/10.2105/AJPH.2022.307167).
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