Diseases Raccoons contract a number of diseases. Distemper occasionally causes raccoons to decline in some locations, but studies show that this is not as common as once thought. Raccoons often are exposed to canine, feline and porcine parvovirus, but to date there is no evidence that raccoons have transmitted this disease to pets or livestock. In Kansas only about 5 percent of raccoons have been exposed to rabies. Exposure means that those tested have rabies antibodies in their blood, indicating they have been attacked but not killed by the virus and they cannot infect other animals.
Raccoons are extremely resistant to the skunk-strain rabies common in the Midwest.
Roundworms have been found in more than 65 percent of the raccoons tested in Iowa. Humans are infected by ingesting eggs contained in the feces, possibly by not washing hands after working in or around a contaminated area. Clinical symptoms depend on how many larvae there are and where they migrate. Larvae migrate to various tissues but cause problems when they enter the eyes or brain. Most adults do not ingest enough eggs to cause brain disease.