First comes the A, then the B: what we learned from the COVID-19 outbreak.

The SARS-CoV-2 epidemic, which has spread to many countries around the world, has hit Europe particularly hard. From our point of view, in a rural emergency department (with an annual patient census of around 25,000) in northeastern Italy, it is necessary to preserve the hospital and prevent it from becoming an outbreak of infection. In our experience, we reevaluated the negative predictive value of lung ultrasound to rule out lung involvement. Since severe acute respiratory failure appears to be the leading cause of death for COVID-19 patients, it is essential to focus on this clinical feature. We currently believe that a patient suspected of COVID-19, if he has a normal ultrasound examination (a so-called "A-profile"), can be discharged home to continue isolation and be treated without being hospitalized.