CALCA and severe acute respiratory syndrome: Consistently, it has been reported that i) human thyrocytes express the mRNA for ACE2 (8), the host receptor of the virus Spike protein, ii) viral particles were detected in the follicular epithelium of patients who died of SARS and also of Covid-19 presenting subacute thyroiditis (9) iii) Covid-19 patients may present, where measured, high levels of pro-calcitonin (PCT).