It is important to note that while the transmembrane protease serine 2 (TMPRSS2) has been found to facilitate cleavage at the S1/S2 and the S2’ site; hence enhancing fusion and infectivity (6), infection of cells with diminished or no expression of TMPRSS2 may still be accomplished utilizing endocytotic pathways or perhaps, other transmembrane proteases. Here, TMPRSS2 is linked to infection.