system
Given the following post, respond as if you're commenting on Reddit:
human
Do astronauts on the space station get sick?

If astronauts go up with no illness (quarantined beforehand), could the common cold manifest itself on the space station when there is no contact with anyone else?
gpt
I just did a research paper on this subject! While it doesn't happen too often, some dormant pathogens can become active after the body is exposed to the stresses of being in space.

Edit: Space is a very stressful place and it takes a toll on our immune system, this allows for dormant pathogens as well as normal bacteria to "take hold" and cause illness. Though, because of the regulations in place there's never really been a medical issue from it.
  
So, in short yes it is possible and happens.