Animal health is of great importance, in agricultural, food security, general economic and public health terms. The diseases that our lab investigates (e.g. tuberculosis, anaplasmosis, Johne's disease, leptospirosis, and porcine reproductive and respiratory syndrome virus (PRRSV)) cause billions of dollars in losses to U.S. agricultural producers. In addition, tuberculosis,anaplasmosis, leptospirosis and Johne's disease are zoonotic diseases, in which animals can serve as reservoirs and vectors of often fatal diseases for humans. For example, Mycobacterium tuberculosis and Mycobacterium bovis, the bacteria that cause tuberculosis, infect one- third of the world's human population, and are responsible for 1.5 million human deaths worldwide per year. While Mycobacterium bovis infection of livestock and humans has been nearly eliminated in the U.S. by decades of culling infected animals and pasteurizing milk, importation of infected livestock and dairy products from Mexico and infected deer reservoirs have resulted in cattle and human infection and deaths in the U.S. The rise in consumer demand for "raw" unpasteurized milk also increases the danger of a tuberculosis outbreak caused by Mycobacterium bovis. History has shown that the best way to treat disease is to prevent it through vaccination, with the long-term goal of driving it into extinction.