Method of the what using genetically modified huge viral (CMV) induction of conditional replication defect type cell to the immune response of CMV is closed in system of the present invention. The method of the present invention can treat with what and/or prevent primary cmv infection, because of CMV reactivations of hiding caused by infection, and the not homophyletic CMV of previous encountered infects (super-infection) again. The present invention also closes what replication defect type CMV, has recombinated change to allow external control virus replication. The present invention also covers the composition comprising replication defect type CMV.
