Addition of 100 mug of polyadenylic: polyuridylic (poly A:U) complex to each dose of inactivated rabies vaccine increased immunity to rabies challenge in mice. Stimulation was also observed after addition of 10 mug of poly A:U to the vaccines. Mixtures of rabies vaccine and poly A:U lost their stimulatory properties after storage at 37 or 4 C for 1 month. However, these data are encouraging for...