ACE2 and infection: Recently, models for SARS-CoV-2 Spike (S)-angiotensin I converting enzyme 2 (ACE2) host receptor interactions support that animal species with close-to-human S-ACE2 interactions (e.g., great apes or ruminants) may constitute effective hosts for maintenance and zoonotic transmission of the virus while other animal species with low S-ACE2 interaction capacity (e.g., cats or pigs) may be susceptible to reverse zoonotic transmission with low risk for human infection [31].