What is known about the origin of SARS-CoV-2?
The coronavirus family has caused zoonotic diseases such the Middle East Respiratory Syndrome (MERS). While a direct ancestor of SARS-CoV-2 is unknown, it is closely related to β-coronaviruses in bats and pangolins, which are likely its original reservoir. SARS-CoV-2 could have risen by selection in the animal host followed by zoonotic transfer and acquisition of further mutations in humans. It is possible that, during undetected human-to-human transmission, the virus mutated, optimizing the binding of its spike protein to human angiotensin-converting enzyme 2 (ACE2). Importantly, available SARS-CoV-2 genetic data do not evince an intentional human manipulation of the virus.6