Incidence of Epstein-Barr virus in astronaut saliva during spaceflight.

BACKGROUND Astronauts experience psychological and physical stresses that may result in reactivation of latent viruses during space-flight, potentially increasing the risk of disease among crewmembers. HYPOTHESIS The shedding of Epstein-Barr virus (EBV) in the saliva of astronauts will increase during spaceflight. METHODS A total of 534 saliva specimens were collected from 11 EBV-seropositive astronauts before, during, and after four space shuttle missions. The presence of EBV DNA in saliva, assessed by polymerase chain reaction (PCR), was used to determine shedding patterns before, during, and after space-flight. RESULTS EBV DNA was detected more frequently before flight than during (p < 0.001) or after (p < 0.01) flight. No significant difference between the inflight and postflight periods was detected in the frequency of occurrence of EBV DNA. CONCLUSIONS The increased frequency of shedding of EBV before flight suggests that stress levels may be greater before launch than during or after spaceflight.