Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated symptoms, named coronavirus disease 2019 (COVID-19), have rapidly spread worldwide, resulting in the declaration of a pandemic. When several countries began enacting quarantine and lockdown policies, the pandemic as it is now known truly began. While most patients have minimal symptoms, approximately 20% of verified subjects are suffering from serious medical consequences. Co-existing diseases, such as cardiovascular disease, cancer, diabetes, and others, have been shown to make patients more vulnerable to severe outcomes from COVID-19 by modulating host-viral interactions and immune responses, causing severe infection and mortality. In this review, we outline the putative signaling pathways at the interface of COVID-19 and several diseases, emphasizing the clinical and molecular implications of concurring diseases in COVID-19 clinical outcomes. As evidence is limited on co-existing diseases and COVID-19, most findings are preliminary, and further research is required for optimal management of patients with comorbidities.

Department of Bioengineering University of Massachusetts Dartmouth Dartmouth MA United States

Department of Biomedical Engineering University of California Irvine Irvine CA United States

Department of Chemical and Biomolecular Engineering New York University New York NY United States

Department of Electrical Engineering University of California Irvine CA United States

Department of Medicine Albert Einstein College of Medicine Bronx NY United States

Department of Neurosurgery University Hospital Basel Basel Switzerland

Division of Hematology Oncology Department of Medicine Rhode Island Hospital and Warren Alpert Medical School of Brown University Providence RI United States

Institute of Parasitology Biology Centre Czech Academy of Science Ceske Budejovice Czech Republic

Laboratory for Integrated Nano Bio Electronics Innovation The Henry Samueli School of Engineering University of California Irvine Irvine CA United States

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