Infectious disease represents one of the largest cost components to the swine industry, incurring veterinary costs, loss of pigs due to mortality, reduced performance, and reduced animal welfare. Strategies to reduce the incidence and impact of infectious disease include biosecurity, vaccination, and routine use of medications, therapeutically or metaphylactically. However, effective vaccines are only available and/or efficacious for some pathogens, while biosecurity protocols that keep most infectious pathogens out may be less effective in hog-dense regions.