Take one salmonella bacteria, dress it in blue body suit, red briefs, and paste a big S on it's chest, don't forget the cape! Look! Up in the atmosphere! It's a chicken, no it's an egg, no it's SuperBug!
Scientists tested what happens when you take bacteria, salmonella to be exact, up into space, give it something to chew on, then bring it home and test it's virulence on lab mice. The result: the mice infected with space raider salmonella got sicker, faster, and deadlier than mice infected with earthborne bugs. Ay caramba, Mickey Mouse and Minney got sick!
So now what? Whither man goeth, so doth the bugth. If we dream of eventually colonizing Pluto, or whatever took it's place in the line of planets, we're sure to bring along our dregs. And I'm not talking certain politicos, but basic one or two cell organisms that love to break us down to our mortal coils. Just like Captain Cook brought forth the destruction of the dodo bird, when we head up and outward, we're likely to expand the nature and power of our wonderfully symbiotic bugs and viruses.