New research has revealed those going on long missions to destinations like the Red Planet could experience the disease awakening within their immune systems. The disease is a dormant virus, but astronauts may see symptoms develop during longer space trips. The study, which was published in Frontiers in Microbiology, also revealed that more than half of crew aboard Space Shuttle and International Space Station missions reactive the skin disease.
Dr Satish Mehta, senior author of KBR Wyle at the Johnson Space Center, said: “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.
“This physical challenge is compounded by more familiar stressors like social separation, confinement and an altered sleep-wake cycle.”
Dr Mehta added: “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.
“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.
“Only six astronauts developed any symptoms due to viral reactivation.”
Four of the eight known human herpes viruses were detected.
The herpes virus stays in the hosts body for the rest of their lives.
Viruses include chickenpox, shingles and, most prominently, oral and genital herpes.
Dr Mehta said developing countermeasures against the virus is a top priority and essential to the success of deep space missions.
Only a small proportion of astronauts develop symptoms but virus reactivation rates increase with spaceflight duration.
Genital herpes is a sexually-transmitted-disease passed on through vaginal, anal and oral sex.
Symptoms include small blisters that burst to leave red, open sores, tingling or itching around genitals or pain when using the toilet.