Infectious diseases are rooted in unsustainable and unjust human–animal relationships. Zoonoses are facilitated by human proximity to animals, epidemiological risk embedded within factory farms, and exploitation of animals and humans in these intensive livestock production systems. The five major categories of epidemiological risk that factory farms propel include: intensification of production for which homogenous populations are congregated, creation of multi-species farms for which different animals are held within the same farm, long and intensive animal transport increases the likelihood of interaction with other wildlife, ecological characteristics of the pathogen lead to altered pathogen dynamics and antibiotic resistance within a human population through the overuse of antibiotics. Layer and broiler operations in the North American context illustrate these linkages. One Health is offered as a concluding conceptual and aspirational frame for pursuing a more sustainable and just world. This article offers two main messages. First, our relationships with animals directly impact the health of human populations through the transmission and creation of Emerging Infectious Diseases (EIDs). Second, adopting One Health offers a means forward for more just and sustainable human–animal relations and reduction of zoonoses transmission.