Moreover, the ability to engage ACE2 from different animal species appears to reflect host susceptibility to SARS-CoV infection and facilitated the jump of the virus from animals to humans. The investigation reported that SARS-CoV-2 uses hACE2 as an entry receptor and recognizes it with a similar affinity to the 2002-2003 SARS-CoV isolates, which suggests it can spread efficiently in humans, in agreement with the numerous SARS-CoV-2 human-to-human transmission events reported to date.