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Raccoon Roundworm

What is Raccoon Roundworm (Baylisascaris procyonis)?

Raccoon roundworm is the infection by a roundworm called Baylisascaris procyonis carried by raccoons. This worm can infect people and a variety of other animals, including dogs. Human infections are rare, but can be severe if the worm invades the eye, organs, or the brain. People living in an area where raccoons live are at greatest risk for raccoon roundworm.

How is it spread?

Humans may be infected with raccoon roundworm after eating the eggs of this worm (Baylisascaris procyonis) passed in the feces (waste) of raccoons. Most infections are seen in children and others who may put dirt or animal waste in their mouths by mistake.

What are the symptoms?

Possible signs and symptoms of raccoon roundworm infection include nausea, tiredness, liver enlargement, loss of coordination, lack of attention to people and surroundings, loss of muscle control, blindness, and coma. Symptoms will develop within 1 to 4 weeks after an exposure.

How is raccoon roundworm treated?

To date, no treatments are known to be completely effective against the disease. Certain medications can help in some cases. Your healthcare provider will discuss your treatment options with you.

How can I prevent raccoon roundworm?

If raccoons are living near your home, you should carefully remove all raccoon feces and any materials that become contaminated with feces. These substances should be buried or thrown away. Care should be taken not to contaminate your hands or clothing, such as wearing rubber gloves and use a shovel while removing feces. Outdoor spaces (such as patios or porches) can be carefully cleaned with boiling water.

Do not keep, feed, or adopt wild animals, including raccoons, as pets.

Sandboxes should be covered whenever they are not in use so raccoons and other wild animals do not use them as bathrooms.

Always wash your hands after working or playing outdoors.​

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