Despite the harsh conditions of the International Space Station, it is not causing microbes to mutate into antibiotic-resistance superbugs.
A new study from Northwestern University, Illinois, US, has found that the microbes are responding to survive in the stressful environment on the International Space Station but, crucially, are not mutating into superbugs harmful to humans.
As conversations about sending space travellers to Mars increase, so too does the interest in understanding how microbes behave in the enclosed environment of the International Space Station.
Erica Hartmann led the study. She said: “There has been a lot of speculation about radiation, microgravity and the lack of ventilation and how that might affect living organisms, including bacteria. These are stressful, harsh conditions. Does the environment select for superbugs because they have an advantage? The answer appears to be ‘no.'”
Analysing the microbes
The team analysed data on the genomic analyses of many of bacteria isolated from the International Space Station. This was obtained from The National Center for Biotechnology Information which maintains a publicly available database of the microbes.
The research team compared the strains of Staphylococcus aureus and Bacillus cereus on the International Space Station to those on Earth.
S. aureus is found on human skin and contains the MRSA strain, while B. cereus lives in soil and has fewer implications for human health.
Ryan Blaustein, a postdoctoral fellow in Hartmann’s laboratory and the study’s first author, explained: “Based on genomic analysis, it looks like bacteria are adapting to live — not evolving to cause disease. We didn’t see anything special about antibiotic resistance or virulence in the space station’s bacteria.”
Spreading illness in space
Although this is positive news for astronauts, Hartmann and Blaustein note that people can still spread illness on space stations.
Hartmann explained: “Everywhere you go, you bring your microbes with you. Astronauts are exceedingly healthy people. But as we talk about expanding space flight to tourists who do not necessarily meet astronaut criteria, we don’t know what will happen. We can’t say that if you put someone with an infection into a closed bubble in space that it won’t transfer to other people. It’s like when someone coughs on an airplane, and everyone gets sick.”“