Diseases which can pass between animals and humans (zoonoses) have been headline news several times in the last ten years. This paper looks at bovine tuberculosis (bTB) in the United Kingdom, which, although not a major health hazard for humans, has been problematic for farmers and the veterinary health institutions. At its current rate of spread, the disease will cost the authorities £1 billion in compensation to farmers for slaughtered animals and in administrative expenses over the next decade. The present Coalition government is planning to cull badgers in England because they are the principal wildlife reservoir of bTB and are said to pass infection to cattle. We argue in five stories that the heterogeneities of bTB help explain the difficulties in dealing with it. In our opinion, the present reductive set of policies would be improved by taking this ontological multiplicity into account.