Alien viruses that enter the Earth through returning spacecraft could be dangerous to humans, scientists have admitted.
16:45 20 February 2017
Experts are concerned about extraterrestrial bacteria or viruses that invade the Earth through returning spacecraft. They said that the human immune system may be powerless against them.
Dr John Rummel, senior scientist at the Seti Institute in Mountain View, California, said that any bacteria or bugs that enter our planet will be contained until testing deems them harmless.
"If we bring samples back from either Europa or Mars, we will contain them until hazard testing demonstrates that there is no danger and no life, or continue the containment indefinitely while we study the material.
"It is assumed that such life would be hardy - to survive the trip to Earth; not easy - and precautions taken would provide a very high degree of containment."
He added: "Microbial life, as a whole, is pretty immune to cold, dry conditions," he said.
"Introduced to the intense radiation around Europa, exposed microbes should die off in hours to days to weeks, but organisms protected inside the spacecraft would still be alive as long as the silicon chips are functioning."