Severe and very severe form: Usually occurs seven days after the infection. Dyspnea and/or hypoxemia may occur in patients with severe forms of the disease, with rapid progression to Acute Respiratory Distress Syndrome (ARDS), septic shock, and acidosis. In critical/very severe patients, severe metabolic alterations, coagulation deficiency, and multiple organ failure can occur. The rise in body temperature in these patients may be mild or absent.