Comparative Efficacy of Commercial Vaccines in NaTve Horses: Serologic Responses and Protection After Influenza Challenge

摘要

The serologic responses of naive horses to tetanus, influenza, and equine herpesvirus (EHV) antigens varied markedly among vaccines registered in the United States. After live influenza virus challenge, variation in the degree of protection against the development of clinical signs and viral shedding was also observed among vaccine groups. All vaccine groups were protected against weight loss. Aside from the publications related to the blinded, randomized controlled challenge trials of a cold-adapted, modified-live virus influenza vaccine (Flu Avert), no data have been published in peer-reviewed literature demonstrating efficacy of the equine vaccines marketed in North America. This, along with published reports of failure of vaccinated animals to mount an adequate immune response and disease in vaccinated animals, has led to concerns regarding the efficacy of these vaccines.