Space

Spaceflight found to reactivate dormant viruses in astronauts

Spaceflight has been found to lower the immune system and reactivate dormant viruses in a human body
Spaceflight has been found to lower the immune system and reactivate dormant viruses in a human body
View 1 Image
Spaceflight has been found to lower the immune system and reactivate dormant viruses in a human body
1/1
Spaceflight has been found to lower the immune system and reactivate dormant viruses in a human body

There are certainly a whole host of technological hurdles to overcome before humans successfully travel to Mars, or beyond, but research is also pointing to a growing assortment of fundamental health challenges that astronauts may face from long stretches of time in space. A recent NASA-funded study has found dormant viruses can reactivate in the human body during spaceflight, presenting yet another physiological problem for scientists to solve before we journey out into deep space.

"NASA astronauts endure weeks or even months exposed to microgravity and cosmic radiation – not to mention the extreme G forces of take-off and re-entry," says Satish K. Mehta from the Johnson Space Center, and senior author on the new study. "This physical challenge is compounded by more familiar stressors like social separation, confinement and an altered sleep-wake cycle."

Prior research has revealed prolonged space travel could result in everything from a heightened cancer risk and neurological degeneration to tissue damage in the gastrointestinal tract. It has also been suggested that spaceflight has a detrimental effect on the immune system and it is this process that scientists are hypothesizing allows dormant viruses to reactivate.

"During spaceflight there is a rise in secretion of stress hormones like cortisol and adrenaline, which are known to suppress the immune system," says Mehta. "In keeping with this, we find that astronaut's immune cells – particularly those that normally suppress and eliminate viruses – become less effective during spaceflight and sometimes for up to 60 days after."

The new research looked at bodily fluid samples from astronauts before, during, and after missions to space. Epstein–Barr virus (EBV), varicella-zoster virus (VZV), and herpes-simplex-1 (HSV-1) were all found to have reactivated and shed into saliva and urine samples in more than half of the studied astronauts. In most cases these astronauts did not develop any specific viral symptoms, however these are infectious viruses and they can increase the chances of adverse medical events occurring on longer space voyages.

The level of viral shedding tracked in the astronaut samples seemed to increase in both frequency and quantity during the longer International Space Station missions. This suggests the immune system dysregulation that may be causing the viral reactivation is not just an acute stress reaction from the initial journey into space.

"The magnitude, frequency and duration of viral shedding all increase with length of spaceflight," explains Mehta.

The researchers hypothesize partial-gravity environments may have the potential to curtail this viral reactivation but certainly suggest more research is needed to better understand how the immune system could be modulated by gravity. In the short term the solution to this particular viral reactivation problem may be better and more targeted vaccination protocols for deep space astronauts.

The new study was published in the journal Frontiers in Microbiology.

Source: Frontiers via ScienceDaily

7 comments
guzmanchinky
We have a lot to learn still, before we can conquer space...
MatthewAtkinson
It's time we stop beating around the bush and get some artificial gravity up there!
mrfixitrick
Thank-you for this article! Viruses will be the biggest issue for mankind in Space. The immune system gets weaker without the gravitational and magnetical fields of the Earth that we are used to. The Keshe Foundation is a space-based organization. Solutions for virus control is an important part of the research and development that the Keshe Foundation offers. Here's a short video from the Keshe foundation that explains the importance of virus research: "Farming Blueprint Day - New Breakthrough In The World Of Science" https://www.youtube.com/watch?v=Dde5uAKthJE Viruses were discussed recently during the Farming Blueprint Day, specifically the treatment for Swine Fever virus in pigs. Playlist: https://www.youtube.com/playlist?list=PLpCKWzA-bp9s0qHaOOB3shYJ81LpgCdlt
bwana4swahili
It is becoming more obvious with each of these 'discoveries' than an organic creature is not designed for space travel. Emphasis should be placed on developing AI systems capable of handling our space travel demands until such time as we evolve beyond our fragile organic origins!
EZ
"presenting yet another physiological problem for scientists to solve before we journey out into deep space." I thought we went way out in deep space way back in '69.
Douglas Bennett Rogers
In a hundred years, or so, old folks with money will be living in .2 g O'Neil cylinders or lunar habitats and will shun the surface of the Earth. I suspect that some of our ancestors lived in such places!
uday pasricha
Strange how science looks at our presence & existence as a stand alone event unconnected to the solar rotation, magnetic forces, solar power and of course gravity. All these hold us and our insides not only in place but in check. If AI is getting mature & advanced then the chess playing robot must be the one to go often till we can grow life on a new planet.