For vaccination of healthy horses 6 months of age or older, as an aid in the prevention of disease caused by Eastern and Western encephalomyelitis viruses and tetanus, as an aid in the control of respiratory disease caused by EIV, Equine Herpesvirus types 1 and 4 (EHV-1 and EHV· 4), and as an aid in reduction of virus shedding of EIV and EHV-1. Duration of immunity(D01) has been shown to be at least six months for EIV.