Alexander Gerst during a spacewalk
Alexander Gerst during a spacewalk
Besides microgravity and radiation, a variety of stress factors such as isolation, heavy workloads and disruption of sleep rhythms can weaken the immune system. On Earth, healthy and, in particular, critically ill people have to cope with comparable problems with their immune system, in some cases triggered by these very stress factors. In both cases, the subjects should be able to put up a sufficient defence against germs, but the immune system should not be falsely activated or over-activated.
Credit:
NASA/ESA.