TMPRSS2 and COVID-19: As already mentioned, it is acknowledged that this systemic effect is a consequence of the modality that this virus has interacting with the host cell: the coronavirus spike binds to angiotensin-converting enzyme 2 (the membrane-bound form) and TMPRSS2 that are found in the lungs, but also in the heart, vessels, kidneys, small intestine epithelium, liver, testicles, ovaries, etc., representing an explanation of COVID-19 multi-system impact [22,23,24].