The international space station can be a little too clean
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The strategy of keeping the spacecraft as clean and sterile as possible to ensure that astronauts do not become sick can be an error. Our immune systems may require stimulation of certain types of molecules and microbes to stay healthy, say that researchers who have studied the International Space Station (ISS).
“The general notion is to try to have as few microbes as possible, but the question is whether it is the best thing to do for long -term space trips,” explains Pieter Dorrestein at the University of California San Diego. “And it is also relevant for places on earth, such as research (stations), hospitals and submarines, where you can spend months or more.”
One of the reasons to sterilize spaceships is to avoid Contaminating planetsLike Mars, with earth microbes, but the main concern is that an infection that would be easily treatable on our planet could become a major problem on a spacecraft.
Dorrestein and his team analyzed more than 700 surface escapes aboard the ISS, and found that it was indeed grumpy in terms of diversity of molecules and microbes present.
“The space station is just devoid of many molecules and microbes,” he said. “It is at the extreme end of human life.”
The team thinks that this lack of exposure with a wide range of usual molecules and microbes could be one of the reasons why there are significant changes in immune system in space. On the space station, astronauts often obtain rashes, unusual allergies, fungal or bacterial infections, as well as the activation of latent viruses such as Epstein-Barr, which was found in one of the samples.
“We don't have a complete understanding of this,” said Dorrestein. “But the way I see this is that your immune system must be periodically crazy.”
Researchers say we have to find ways to make environments like the space Station “dirtier, so that they are more diversified in molecules and microbes, but without introducing pathogens causing an infection”.
One way to do it would be to apply bacteria such as Bacillus subtilis To surfaces instead of disinfectants, explains Dorrestein. B. Subtil is already widely used for its antifungal activity.
Cultivate a range of plants could also help. “We know by other studies that when people are exposed to many more plant molecules, they tend to reduce links with asthma and allergies,” explains Dorrestein. There is a complete absence of these vegetable molecules on the space station, he says.
