`` Furthermore , genetic similarities virus backbones used known reverse genetics systems betacoronaviruses.This suggests virus engineered . `` Another COVID-19 feature , furin cleavage site , allows virus infect human cells , diminishes tissue culture , Andersen said . `` I think could probably still infect people , I think much less efficiently , '' added.Furthermore , questions anyone would go work creating new virus could simply take existing virulent pathogen like SARS ( severe acute respiratory syndrome ) MERS ( Middle East respiratory syndrome ) coronaviruses make even worse , bioweapons programs far done . `` It n't make sense make new virus n't know cause disease humans try create bioweapon , '' Andersen said . `` That would really bad bioweapons person . `` Conspiracy theory # 2 : Lab release natural virus For many years around world , scientists studied bat coronaviruses capturing bats caves isolating growing tissue culture coronaviruses carry see infect human cells .