Elevated stress hormone levels relate to Epstein-Barr virus reactivation in astronauts

Objective: The objective of this study was to determine the effects of stre ss and spaceflight on levels of neuroendocrine hormones and Epstein-Barr vi rus (EBV)-specific antibodies in astronauts. Methods: Antiviral antibody ti ters and stress hormones were measured in plasma samples collected from 28 astronauts at their annual medical exam (baseline), 10 days before launch ( L-10), landing day (R+0), and 3 days after landing (R+3). Urinary stress ho rmones were also measured at L-10 and R+0. Results: Significant increases ( p < .01) in EBV virus capsid antigen antibodies were found at all three tim e points (L-10, R+0, and R+3) as compared with baseline samples. A-nti-EBV nuclear antigen antibodies were significantly decreased at L-10 (p < .05) a nd continued to decrease after spaceflight (R+0 and R+3, p < .01). No chang es were found in antibodies to the nonlatent measles virus. The 11 astronau ts who showed evidence of EBV reactivation had significant increases in uri nary epinephrine and norepinephrine as compared with astronauts without EBV reactivation. Conclusion: These findings indicate that physical and psycho logical stresses associated with spaceflight resulted in decreased virus-sp ecific T-cell immunity and reactivation of EBV.