The differential impact of training stress and final examination stress on herpesvirus latency at the United States Military Academy at West Point

In this study, we searched for evidence for reactivation of three latent herpesviruses, Epstein-Barr virus (EBV), herpes simplex virus type-1 (HSV-1), and human herpesvirus 6 (HHV-6), in West Point cadets experiencing two different stressors. Blood samples were obtained from cadets before and after a 6-week training period known as "Cadet Basic Training" (CBT), at a baseline prior to final examinations, and then once again during the week of final examinations. Antibody titers to latent HSV-1, EBV, and HHV-6 were determined as a measure of the steady-state expression of latent virus. EBV virus capsid antigen (VCA) IgG antibody titers were unchanged in blood samples obtained prior to and immediately after CBT. However, EBV antibody titers were significantly higher in the blood sample obtained during examination week than in the baseline period before examination; they were also higher than antibody titers before/after CBT. None of the serum samples were positive for EBV VCA IgM antibodies, indicating that the changes in antibody titers to EBV were not associated with recent EBV infections in the class. No significant changes in antibody titers to HSV-1 or HSV-6 were found over the identical time periods, including examination week. Academic stress but not CBT modulated the steady-state expression of latent EBV, resulting in the reactivation of latent virus. The same stressors, however, did not affect the steady-state expression of latent HSV-1 or HSV-6, at least as measured by changes in antibody titers. The data provide additional evidence of the impact of different psychological stressors on the steady-state expression of latent herpesviruses. (C) 1999 Academic Press.