Defining and testing a wildlife intervention framework for exotic disease control

Outbreaks of disease at the wildlife-livestock interface may require management interventions. Where they involve exotic/non-endemic pathogens in wildlife, then such plans may need to be rapidly conceived and implemented to prevent further disease spread. However, detailed information on the distribution of infection is likely to be absent, whilst limited resources and tools, and ethical considerations impose constraints on what is possible and proportionate.We describe four considerations to inform decision-making on whether to intervene. With reference to two recent examples (bovine tuberculosis in badgers in an otherwise disease-free area, and African swine fever in wild boar in central Europe), we outline six steps to guide implementation.In both examples, a Disease Control Area was defined by determining a minimum infected area (MIA) and a buffer zone based on wildlife ecology and the potential for unrecorded spread of infection. The total area was the subject of management intervention, with the level of infection used to inform adaptive management.The MIA is defined as the minimum area that could contain all infected wildlife, given our current level of information, with a surrounding buffer zone to account for the possibility of further onward spread. In our examples, the zones were defined using a combination of field data and existing knowledge of host spatial organization and movement.The MIA (plus buffer zone) approach provides a framework for optimizing the targeting of resources in a proportionate response to a disease outbreak. Where infected animals occur outside the MIA, our examples show how wildlife management has been adapted. In principle, this approach is suitable for the delivery of disease outbreak control in wildlife, whether through culling, vaccination or other forms of control.