On Farms
Opossums can threaten the livestock and crops on a farm. The opossum̵7;s diet is varied and can include corn and poultry. Opossums have been known to raid farm outbuildings at night to steal chickens, according to the University of Massachusetts, Amherst. Ducks and turkeys are also at risk; owners should enclose these animals in secure pens to keep opossums from reaching them.
Dangers to Pets
Opossums aren't strong enough to pose a danger to most pets. Cats and dogs are likely to avoid or even injure opossums in an encounter. Though opossums can bite pets, the larger threat is in the diseases they may carry. Substantial evidence exists that opossums can pass the disease equine protozoal myeloencephalitis to horses, according to the Washington Department of Fish and Wildlife. This parasitic organism attacks a horse̵7;s nervous system. Horse owners should cover food and grain in horse enclosures to reduce the chance of attracting opossums. Opossums can also carry fleas, which can jump onto household pets such as cats when an opossum dies nearby.
Bites
The opossum has a mouth full of teeth and can bite humans or other animals painfully if provoked. Opossums are typically placid creatures, though, and generally will bite only if the opossum feels threatened, especially if cornered, or if it thinks that its young are in danger. Humans who find opossums inside their homes or in their back yards should leave the area and allow the creature to remove itself in its own time. Avoiding confrontations with the opossum reduces the risk of bites.
Disease to Humans
Opossums aren̵7;t associated with any specific disease that they can pass to humans. Many animals can pass on serious diseases, though, so people who encounter an opossum, alive or dead, should wear rubber gloves to touch the creature. Like all mammals, opossums can carry rabies, but scientists have found that opossums have a lower-than-average risk of carrying this disease. According to the Opossum Society website, this is thought to be due to the opossum̵7;s low body temperature, an inhospitable environment for rabies.