The coronavirus disease 2019 (COVID-19) pandemic has created unprecedented challenges worldwide. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 and has a complex interaction with the immune system, including growing evidence of sex-specific differences in the immune response. Sex-disaggregated analyses of epidemiological data indicate that males experience more severe symptoms and suffer higher mortality from COVID-19 than females. Many behavioural risk factors and biological factors may contribute to the different immune response. This review examines the immune response to SARS-CoV-2 infection in the context of sex, with emphasis on potential biological mechanisms explaining differences in clinical outcomes. Understanding sex differences in the pathophysiology of SARS-CoV-2 infection will help promote the development of specific strategies to manage the disease.

Department of Bioengineering University of Massachusetts Dartmouth Dartmouth Massachusetts USA

Department of Biomedical Engineering University of California Irvine Irvine California USA

Department of Electrical Engineering University of California Irvine Irvine California USA

Department of Medicine Albert Einstein College of Medicine Bronx New York USA

Department of Molecular Microbiology and Immunology Brown University Providence Rhode Island USA

Department of Neurosurgery University Hospital Basel Basel Switzerland

Laboratory of Functional Biology of Protists Institute of Parasitology Biology Centre of the Czech Academy of Sciences České Budějovice Czech Republic

Wallace H Coulter Department of Biomedical Engineering Emory University School of Medicine and Georgia Institute of Technology Atlanta Georgia USA

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