Abstract: nutrients Article Low Zinc Levels at Admission Associates with Poor Clinical Outcomes in SARS-CoV-2 Infection Marina Vogel-González 1,† , Marc Talló-Parra 2,† , Víctor Herrera-Fernández 1 , Gemma Pérez-Vilaró 2 , Miguel Chillón 3,4,5 , Xavier Nogués 6 , Silvia Gómez-Zorrilla 7 , Inmaculada López-Montesinos 7 , Isabel Arnau-Barrés 7 , Maria Luisa Sorli-Redó 7 , Juan Pablo Horcajada 7 , Natalia García-Giralt 6 , Julio Pascual 8 , Juana Díez 2,‡ , Rubén Vicente 1,‡ and Robert Güerri-Fernández 7, *,‡ 1 2 3 4 5 6 7



 8 Citation: Vogel-González, M.; Talló-Parra, M.; Herrera-Fernández, V.; Pérez-Vilaró, G.; Chillón, M.; Nogués, X.; Gómez-Zorrilla, S.; * † ‡ Laboratory of Molecular Physiology, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, 08003 Barcelona, Spain; marina.vogel@upf.edu (M.V.-G.); victor.herrera01@estudiant.upf.edu (V.H.-F.); ruben.vicente@upf.edu (R.V.) Molecular Virology Group, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, 08003 Barcelona, Spain; marc.tallo@upf.edu (M.T.-P.); gemma.perez@upf.edu (G.P.-V.); juana.diez@upf.edu (J.D.) Department of Biochemistry and Molecular Biology and Institute of Neurosciences, Edifici H, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain; Miguel.Chillon@uab.cat Unitat Mixta UAB-VHIR, Vall d’Hebron Institut de Recerca (VHIR), 08035 Barcelona, Spain Institut Català de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain Department of Internal Medicine, Hospital del Mar, Institut Mar d’Investigacions Mediques, 08003 Barcelona, Spain; xnogues@psmar.cat (X.N.); ngarcia@imim.es (N.G.-G.) Department of Infectious Diseases, Hospital del Mar, Institut Mar d’Investigacions Mediques, 08003 Barcelona, Spain; SGomezZorrilla@parcdesalutmar.cat (S.G.-Z.); ilopezmontesinos@psmar.cat (I.L.-M.); iarnau@psmar.cat (I.A.-B.); lsorli@psmar.cat (M.L.S.-R.); jhorcajada@psmar.cat (J.P.H.) Department of Nephrology, Hospital del Mar, Institut Mar d’Investigacions Mediques, Autonomous University of Barcelona, 08003 Barcelona, Spain; JPascualSantos@parcdesalutmar.cat Correspondence: rguerri@psmar.cat; Tel.: +34-932-483-251; Fax: +34-932-483-249 Both authors contributed equally to the work. J.D., R.V. and R.G.-F. are joint senior authors in this work. López-Montesinos, I.; Arnau-Barrés, I.; Sorli-Redó, M.L.; et al. Low Zinc Levels at Admission Associates with Poor Clinical Outcomes in SARS-CoV-2 Infection. Nutrients 2021, 13, 562. https://doi.org/10.3390/ nu13020562 Received: 8 January 2021 Accepted: 30 January 2021 Published: 9 February 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Copyright: © 2021 by the authors. Abstract: Background: Zinc is an essential micronutrient that impacts host–pathogen interplay at infection. Zinc balances immune responses, and also has a proven direct antiviral action against some viruses. Importantly, zinc deficiency (ZD) is a common condition in elderly and individuals with chronic diseases, two groups with an increased risk for severe severe coronavirus disease 2019 (COVID-19) outcomes. We hypothesize that serum zinc content (SZC) influences COVID-19 disease progression, and thus might represent a useful biomarker. Methods: We ran an observational cohort study with 249 COVID-19 patients admitted in Hospital del Mar. We have studied COVID-19 severity and progression attending to SZC at admission. In parallel, we..