The overarching importance of sleep was further emphasized during the pandemic of COVID-19. The subjects infected by COVID-19 frequently experience sleep disturbances; some are long-lasting problems and decrease the quality of life. Insomnia is the most studied sleep disorder associated with COVID-19. Insomnia affects patients who have experienced an infection and the general population. Good sleep is important in maintaining mental and physical health, including immune system functions. The interconnections between insomnia, the immune system, and COVID-19 are complex. Insomnia triggers numerous immune system dysregulations and makes individuals more vulnerable to respiratory infections. This narrative review overviews the influence of the COVID-19 pandemic on the immune system through sleep disorders.

Department of Psychiatry Faculty of Medicine and Dentistry University Palacky Olomouc University Hospital Olomouc The Czech Republic

Department of Psychology Sciences Faculty of Social Science and Health Care Constantine the Philosopher University in Nitra Nitra The Slovak Republic

Department of Psychotherapy Institute for Postgraduate Training in Health Care Prague The Czech Republic

Department of Respiratory Diseases and Tuberculosis University Hospital and Faculty of Medicine and Dentistry Pavol Jozef Safarik University Kosice The Slovak Republic

Department of Respiratory Medicine Faculty of Medicine and Dentistry University Palacky Olomouc and University Hospital Olomouc The Czech Republic

Rehabilitation Hospital Beroun Jessenia Inc Akeso Holding Beroun The Czech Republic

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