 Even though the virus is widespread in rodent colonies and has been used in laboratory research for decades, it has never been observed that it can cause human disease.Moreover, Sendai virus has been used in clinical trials involving both adults and children to immunize against human parainfluenza virus type 1, since the two viruses share common antigenic determinants and trigger the generation of cross-reactive neutralizing antibodies.The Sendai virus administration in the form of nasal drops in doses ranging from 5 × 105 50% embryo infectious dose (EID50) to 5 × 107 EID50 induced the production of neutralizing antibodies to the human virus without any measurable side effects.The results of these trials represent additional evidence of Sendai virus safety for humans.The development of T cell-based AIDS vaccines using Sendai virus vectors reached phase II clinical trial.Evaluation of the safety and immunogenicity of an intranasally administered replication-competent Sendai Virus–vectored HIV Type 1 gag vaccine demonstrated