ACE2 and COVID-19: With the rapid progress that has been made with diagnostic reagents (e.g., nucleic acid and IgM or IgG detection or both), drug repurposing (e.g., remdesivir and chloroquine), immunotherapeutic approaches (e.g., Tocilizumab), and vaccine production as a consequence of the outbreak of novel COVID-19, we thought that it is timely to shed light on the putative link between circulating ACE2 and disease severity.