Recently published in the scientific journal American Journal of Physiology, a Brazilian study demonstrated for the first time that survivors of severe COVID-19 infections may have elevated muscle sympathetic nerve activity (MSNA) in response to mental stress. The study was carried out by the D'Or Institute for Research and Education (IDOR), in partnership with the University of São Paulo (USP), the Federal University of São Paulo (Unifesp), and the University of Colorado Boulder. Its results are a warning for the so-called long covid, chronic sequelae left by the disease that could increase the risk of cardiovascular diseases.