Fig. 7

Similarities and synergy between insulin resistance/obesity/diabetes and COVID-19. COVID-19. In symptomatic patients with COVID-19 the course of the disease can be didactically divided into four phases. Phase 1: Viral entrance in cells is facilitated by ACE2. Phase 1 starts when an individual becomes symptomatic. The most frequent manifestations in this phase are fever and dry cough, and many individuals may lose their senses of taste and smell and feel a general malaise, and for most individuals, the disease is limited to this phase. Phase 1/Phase 2: Immune cell migration to the lungs. Phase 2: Is the pulmonary stage of the disease when individuals develop pulmonary inflammation and pneumonia. In this phase there is an impaired early antiviral interferon response and cytokine storm. Based on the presence or not of hypoxia this phase can be subdivided in 2b or 2a. Most individuals need hospitalization, and some with prolonged hypoxia need mechanical ventilation. Phase 3: the patients develop ARDS and extrapulmonary systemic hyper inflammation syndrome, shock, vasoplegia, respiratory failure, cardiopulmonary collapse, myocarditis, and acute kidney injury, with poor prognosis and increased mortality. Phase 4: Is the recovery and survival stage