William M. Switzer, HaoQiang Zheng, Graham Simmons, Yanchen Zhou, Shaohua Tang, Anupama Shankar, Beatrix Kapusinszky, Eric L. Delwart, Walid Heneine

The association of xenotropic murine leukemia virus (MLV)-related virus (XMRV) in prostate cancer and chronic fatigue syndrome reported in previous studies remains controversial as these results have been questioned by recent data. Nonetheless, concerns have been raised regarding contamination of human vaccines as a possible source of introduction of XMRV and MLV into human populations. To address this possibility, we tested eight live attenuated human vaccines using generic PCR for XMRV and MLV sequences. Viral metagenomics using deep sequencing was also done to identify the possibility of other adventitious agents.