Astronauts’ Dormant Viruses Can Get Reactivated In Space, NASA Says

Space travel comes with a lot of different risks, so it’s not like astronauts need any new hazards to add to that list. But new research published in the journal Frontiers in Microbiology found that the stress of spaceflight is reactivating dormant viruses like herpes in some astronauts, CNN reports. As if space travel wasn’t stressful enough, NASA researchers found the longer astronauts stayed in space, the more likely viruses like herpes, chickenpox, and shingles reactivated in their bodies, according to CNN.

Researchers took samples of astronauts’ blood, urine, and saliva before, during, and after short space shuttle flights and long-term International Space Stations (ISS) missions, says CNN, and they found that herpes viruses reactivated in more than half of the astronauts.

“To date, 47 out of 89 astronauts on short space shuttle flights and 14 out of 23 on longer ISS missions shed herpes viruses in their saliva or urine samples,” Satish K. Mehta of the Johnson Space Center and lead study author of the study told CNN. “These frequencies — as well as the quantity — of viral shedding are markedly higher than in samples from before or after flight, or from matched healthy controls.”

Astronauts are exposed to all kinds of stressors during space flight, like varying gravitational forces, cosmic radiation, social separation, confinement, sleep deprivation, anxiety, and disruption to their circadian rhythms, according to the study. The researchers say spaceflight-associated stressors can increase the effects of stress hormones and, in turn, weaken the immune system. These changes in the astronauts’ immune systems is what the researchers say reactivated the herpes virus in their bodies.

Four out of the eight types of herpes viruses were detected in the astronauts, according to CNN, including oral and genital herpes, chickenpox, and shingles. But just because the virus was detected in the astronauts doesn’t mean they had any symptoms; only six developed any symptoms as a result of viral reactivation, CNN reports.

If these findings seem a little out-of-this-world to you, this research can actually be applied to Earthlings as well. "This research has tremendous clinical relevance for patients on Earth, too,” Mehta told CNN. “Already, our spaceflight-developed technologies for rapid viral detection in saliva have been employed in clinics and hospitals around the world.”

About 90 percent of the U.S. population has herpes simplex virus (HSV) or the closely related virus that can cause chicken pox or shingles, according to Medical News Today. It’s common to not experience any symptoms if you have herpes, says Medical News Today, but the virus still “lays dormant in neurons” and can be reactivated by stress.

“Stress is a huge trigger for herpes outbreaks, so learn and use stress-management techniques. Try modalities like yoga, meditation, acupuncture, and counseling," Madeline Mindich, a licensed acupuncturist, told Everyday Health.

Herpes still carries a huge stigma here in the United States even though, statistically, it’s very likely you know someone who has herpes, NPR reports. There’s no cure for herpes, and it can be transmitted when a person isn’t having symptoms, says NPR, but the virus doesn’t affect fertility or internal organs. Health professionals say that practicing safe sex — and using a barrier method like a condom — is key to preventing the spread of herpes or other STIs, whether you know you have herpes or not, according to NPR.

The key takeaway here is that your stress levels can most definitely affect your immune system, and that paves the way for all kinds of viruses to reactivate in your body. Now you can say your self-care regimen is endorsed by NASA. And who can argue with that?