Raccoons & Public Health

Racoons © Michael Doyle
Racoons © Michael Doyle

Raccoons can transmit disease to other wildlife, domestic animals, and, occasionally, humans. Although there’s no need to panic at the sight of a raccoon walking through your yard, you should avoid contact with raccoons, their feces, and den sites. People should never keep raccoons as pets—it’s illegal and dangerous—nor should they deliberately feed these animals.

A raccoon that appears friendly and approachable may actually be sick, and children should be taught to stay away. If you encounter a sick, injured, or orphaned animal, don’t attempt to handle it; contact your local animal control officer or police department for advice. Discourage raccoons from frequenting your home or yard by eliminating food sources and excluding them from possible den sites.


Health officials confirmed raccoons infected with the rabies virus in Massachusetts in September of 1992, and since that time, the disease has spread to nearly every community in the Commonwealth. The virus, communicable to all mammals including humans, has been working its way northward from West Virginia since the late 1970s. Learn More


Raccoons can carry both canine and feline distemper, both serious diseases caused by different viral agents. Both distempers pose no threat to humans, but can be detrimental to cats and dogs.

Abnormal behavior, disorientation, aggressiveness, and weakness in the hind limbs are all symptoms of distemper. To prevent the spread of disease—transmitted via inhalation of aerosol droplets found in feces, bodily fluids, and possibly contaminated objects—vaccinate your dog or cat.


Roundworm is a host-specific parasite that can mature and reproduce only in the small intestine of raccoons. Raccoons show no ill effects from the intrusion, but health problems can arise if the microscopic eggs, deposited in the raccoon's feces, enter the body of a non-host species.

The sticky eggs adhere to any surface (wood, fur, grass, etc.) and are viable for three to five years.

Wild and domestic animals, birds, and humans are at risk if the eggs come in contact with the eyes or mouth. When larvae hatch in the body of a non-host, they form cysts in muscle, lung, eye, or brain tissue. Effects, which include nervous disorders, eye and coordination problems, and paralysis, can appear within days or weeks, depending on the number of eggs ingested.

Only incineration can destroy the eggs of roundworm, so it’s best to avoid any direct contact with raccoon feces or den sites.

For more information, visit the Massachusetts Department of Public Health.