It may sound like a plot from a science fiction film, but NASA and scientists are concerned about alien viruses contaminating Earth. Although exciting, the mission could be detrimental to Earth if the space faring heroes return carrying alien pollutants. 'But, the [Mars] samples returned by [NASA] will be quarantined and treated as though they are the Ebola virus until proven safe.' Such a procedure will undoubtedly be followed for humans returning from Mars.' Not only are experts concerned about contaminating Earth, they also have fear of humans spreading their germs on Mars.

Source: Daily Mail May 08, 2020 23:02 UTC