West Nile-Innovator® vaccines aid in the prevention of West Nile, equine encephalomyelitis due to Eastern, Western and Venezuelan viruses and tetanus. West Nile-innovator is the veterinarian's first choice for core disease protection and has been shown to provide an immune response to West Nile virus that is four times more than a big one-shot combination vaccine. West Nile virus is fatal in 33% of horses that exhibit clinical signs of disease. Vaccination is the most effective way to help protect horses against West Nile virus and other mosquito-borne diseases, such as Eastern equine encephalitis (EEE) and Western equine encephalitis (WEE). If vaccinated, horses have shown to be 30X less likely to contract West Nile virus. West Nile-innovator vaccines contain the adjuvant Metastim®, which is designed for safe, enhanced presentation of antigens to the horse's immune system. Metastim features a dual-phase formulation shown to stimulate both cell-mediated and humoral immunity to West Nile virus. Only innovator vaccines from Zoetis are adjuvanted with Metastim for improved immune response.