Episodes of Herpes virus Reactivation More Common in Astronauts -  NASA study  | Virus World | Scoop.it

Latent herpes virus reactivation has been documented in more than half of astronauts during space shuttle and International Space Station missions, and according to a recent study funded by NASA, the cause is stress.“Herpes virus is a broad category of viruses, beyond the small subset that cause sexually transmitted diseases.Most humans become infected early in life with one or more, and never fully clear these viruses,” Satish Mehta, PhD, senior scientist in the immunology/virology lab at the Johnson Space Center in Houston, told Infectious Disease News.

 

Results showed that 47 out of 89 (53%) astronauts on short space shuttle flights, and 14 out of 23 (61%) on longer space station missions shed herpes viruses in their saliva or urine samples. According to the study, astronauts shed four of the eight major human herpes viruses: Epstein-Barr, varicella-zoster and herpes simplex-1 in saliva and cytomegalovirus in urine. The researchers said most astronauts were asymptomatic, with only six developing symptoms.

 

“Larger quantities and increased frequencies for these viruses were found during spaceflight as compared to before or after flight samples and their matched healthy controls,” Mehta and colleagues wrote.  Mehta explained why: “[The] short answer is stress. In people with reduced immunity, such as the elderly or stressed individuals, these viruses can awaken and cause disease,” he said.

 

“Although NASA believes there is no clinical risk to astronauts during orbital spaceflight, there is concern that during deep space exploration missions, there may be clinical risks related to viral shedding. Although we do not have a serious clinical problem related to herpes viruses, their reactivation is an excellent ‘flag,’ or biomarker, for stress and reduced immunity.”

In the study, Mehta and colleagues noted that continued viral shedding after a flight can pose a potential risk for crew who may encounter infants, seronegative adults or immunocompromised people, so protocols have been put in place. 

 

The study was published in February 2019  in Frontiers in Microbiology - Virology:

https://doi.org/10.3389/fmicb.2019.00016