How does SARS-CoV-2 targets the elderly patients? A review on potential mechanisms increasing disease severity

•Especially the frail elderly show a high number of severe COVID-19.•Viral shedding may be increased in elderly patients.•Early identification is complicated due to atypical disease presentation.•Applying hygiene measures in patients with cognitive disorders is challenging.•The cardiorespiratory reserve is decreased increasing the risk of complications.•The aging immune system has a pro-inflammatory tendency, exaggerated by SARS-CoV-2.