a1 USDA, APHIS, Veterinary Services, Center for Epidemiology and Animal Health, Fort Collins, CO, USA
Mycobacterium bovis (M. bovis), the causative agent of bovine tuberculosis, has been identified in nine geographically distinct wildlife populations in North America and Hawaii and is endemic in at least three populations, including members of the Bovidae, Cervidae, and Suidae families. The emergence of M. bovis in North American wildlife poses a serious and growing risk for livestock and human health and for the recreational hunting industry. Experience in many countries, including the USA and Canada, has shown that while M. bovis can be controlled when restricted to livestock species, it is almost impossible to eradicate once it has spread into ecosystems with free-ranging maintenance hosts. Therefore, preventing transmission of M. bovis to wildlife may be the most effective way to mitigate economic and health costs of this bacterial pathogen. Here we review the status of M. bovis infection in wildlife of North America and identify risks for its establishment in uninfected North American wildlife populations where eradication or control would be difficult and costly. We identified four common risk factors associated with establishment of M. bovis in uninfected wildlife populations in North America, (1) commingling of infected cattle with susceptible wildlife, (2) supplemental feeding of wildlife, (3) inadequate surveillance of at-risk wildlife, and (4) unrecognized emergence of alternate wildlife species as successful maintenance hosts. We then propose the use of integrated and adaptive disease management to mitigate these risk factors to prevent establishment of M. bovis in susceptible North American wildlife species.
(Received October 31 2012)
(Revised April 01 2013)
(Accepted April 02 2013)
(Online publication May 09 2013)
c1 Author for correspondence: R. S. Miller, 2150 Centre Avenue, Bldg B, Fort Collins, CO 80526, USA. (Email: Ryan.S.Miller@aphis.usda.gov; Ryan.Miller@rsmiller.net)