The concentration of humans and animals in proximity enhances potential transmission of microorganisms among members of the group. It also creates greater potential for infecting surrounding life forms, even those of different species. The industrialization of livestock production and the widespread use of non-therapeutic antibiotics has intensified the risk of new, more virulent, or more resistant organisms. This has reduced the effectiveness of several classes of antibiotics for treating infections in humans and animals.
This Mini-Monograph was originally published in Environmental Health Perspectives. Volume 115, Number 2, February 2007.