Reverse zoonotic transmission (zooanthroponosis): An increasing threat to animal health

The fundamental premise of the One Health concept is that the collective health of humans, animals, and their shared environments depends upon the interactions between each domain. When it comes to mitigating infectious disease risk at this interface, an integrated approach is necessary. While recognition of the threat of animal-to-human disease transmission (zoonosis) is widely understood, there has been less consideration of the potential harm that humans can have on animal populations through reverse zoonosis. This chapter presents evidence and descriptions of human-to-animal disease transmission spanning viruses, bacteria, parasites, and fungi among companion animals, livestock and poultry, and wildlife as well as recommendations for multidisciplinary strategies for prevention and control. Collaborative efforts between veterinary health, public health, and environmental health professionals are critical to address the anticipated increased risk of reverse zoonotic events.