Alien bugs hitching a ride to Earth on spacecraft could ATTACK humans and must never be allowed to escape

Alien bugs could hitch a lift on spaceships to Earth and attack humans, researchers warn.

These extraterrestrial viruses may be a 'danger' to our immune systems, potentially killing large numbers of people.

Scientists say rock and ice samples brought back from Mars or Jupiter’s moon Europa should be isolated forever to mitigate the threat. 

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Alien bugs could hitch a lift on spaceships to Earth and attack humans, researchers warn. These extraterrestrial viruses may be a 'danger' to our immune systems, potentially killing large numbers of people

Dr John Rummel, a senior scientist at the Seti Institute in Mountain View, California spoke about his fears of space contamination at the American Association for the Advancement of Science (AAAS) annual meeting in Boston. 

Dr Rummel said it was 'pretty easy' for alien pathogens to survive space journeys because they are shielded from the sun's ultraviolet radiation. 

He said it was therefore hugely important to isolate material that comes from other planets.

'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', he said.    

Scientists believe Europa has a salty ocean beneath its crust which may harbour simple life. 

Extraterrestrial viruses could be a 'danger' to our immune systems and top scientists have said samples from other planets might have to be contained forever for public safety (stock image)

A patch of land in an ancient valley on Mars may once have been home to salty groundwater – and it could now be a prime target in the search for past life. 

'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.'

'Microbial life, as a whole, is pretty immune to cold, dry conditions,' he said. 

'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.' 

Scientists say rock and ice samples brought back from Mars or Jupiter’s moon Europa (pictured) should be isolated forever to mitigate the threat of alien life invading Earth

The scientist also raised concerns about space equipment from Earth contaminated these foreign worlds.

Dr Rummel said it was essential that there were systems in place to prevent contamination of pristine planets with microbes from earth. 

If organisms from Earth contaminated Europa it would make it much harder to find out the origins of the planet.

'Earth organisms in the Europan ocean could hide the origin of Europan life from science, forever,' said Dr Rummel. 

Mars has such harsh conditions that it was less likely to be affected by bugs carried on spacecrafts. 

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