Fuentes, AnaSerrano-Conde, EstherRoldán, CarolinaBenito-Ruesca, RafaelMejías, GregoriaSampedro, AntonioMarch-Roselló, GabrielFernández-Natal, IsabelEsperalba, JulianaRodríguez, Mario JoséMartínez de Aguirre, PaulaSalas, CarlosRoc, María LourdesSoria, Luis MiguelParra-Grande, MónicaMontero, María DoloresFernández-Roblas, RicardoFranco-Álvarez de Luna, FranciscoLozano, CarmenGarcía, Federico2023-02-092023-02-092021-01-29http://hdl.handle.net/10668/17065To evaluate the serological response against SARS-CoV-2 in a multicenter study representative of the Spanish COVID pandemic. IgG and IgM + IgA responses were measured on 1466 samples from 1236 Spanish COVID-19 patients admitted to the hospital, two commercial ELISA kits (Vircell SL, Spain) based on the detection of antibodies against the viral spike protein and nucleoprotein, were used. Approximately half of the patients presented antibodies (56.8% were IgM + IgA positive and 43.0% were IgG positive) as soon as 2 days after the first positive PCR result. Serological test positivity increased with time from the PCR test, and 10 days after the first PCR result, 91.5% and 88.0% of the patients presented IgM + IgA and IgG antibodies, respectively. The high values of sensitivity attained in the present study from a relatively early period of time after hospitalization support the use of the evaluated serological assays as supplementary diagnostic tests for the clinical management of COVID-19.enAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/COVID-19DiagnosisIgAIgGIgMSARS-COV-2AdolescentAdultAge FactorsAgedAged, 80 and overAntibodies, ViralAntibody FormationCOVID-19COVID-19 Serological TestingCoronavirus Nucleocapsid ProteinsEnzyme-Linked Immunosorbent AssayFemaleHospitalizationHumansImmunoglobulin AImmunoglobulin GImmunoglobulin MMaleMiddle AgedPhosphoproteinsSensitivity and SpecificitySex FactorsSpainSpike Glycoprotein, CoronavirusYoung Adultresearch article33512616open access10.1007/s10096-020-04139-51435-4373PMC7843881https://link.springer.com/content/pdf/10.1007/s10096-020-04139-5.pdfhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC7843881/pdf