Astronauts are falling sick on ISS because it's too clean
What's the story
Astronauts aboard the International Space Station (ISS) have been suffering from a variety of health issues, from persistent rashes and strange allergies to infections from fungi, shingles, and cold sores.
Now, recent research indicates that the root cause of these health problems could be an insufficient amount of germs in the orbiting laboratory.
This is because of a lack of free-living microbes normally found in soil and water on Earth.
Health impact
Microbial imbalance linked to chronic inflammatory diseases
Bacteria that normally reside in or on the human body, come to space with their human hosts. But the diverse pool of free-living microbes found on Earth is absent from the ISS.
This microbial imbalance has been linked to chronic inflammatory diseases.
Scientists think that introducing a variety of microbes into the ISS and its future replacements could actually improve astronaut health.
Sterile environment
Sterile environment: A potential source of health issues
Rob Knight, from the University of California, San Diego's Center for Microbiome Innovation, clarified how exposure to healthy soil differs from a strictly enclosed environment.
He said that in an enclosed space like the ISS, there's no continuous input of healthy microbes from outside sources.
Over 280 astronauts have visited the ISS in its 25-year history. To better understand these conditions, Knight and other researchers collaborated to map the microbes living onboard.
Mapping microbes
Here's what ISS's microbial mapping revealed
The research team discovered that the ISS is more sterile than our living quarters on Earth. The bacteria found on the station were linked to immune-related symptoms.
Astronaut and microbiologist Kathleen Rubins and other crew members swabbed more than 700 surfaces on the space station and over 60 controls.
Most of the bacteria they found were those that live on humans.
Living conditions
Living conditions on ISS may contribute to skin ailments
Rubins suggested that living conditions on ISS could be contributing to some of the skin ailments experienced by astronauts.
She noted that there are no showers on ISS, and they can only use a small amount of water for washing.
Further, astronauts wear their clothes for two weeks straight due to lack of laundry facilities in space.
This unique environment may be impacting their health in unexpected ways.