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Raccoon Roundworm

This fact sheet answers frequently asked questions about Raccoon Roundworm.

Raccoon roundworm is an infection by a roundworm called Baylisascaris procyonis carried by raccoons.

The basics

What is Raccoon Roundworm (Baylisascaris procyonis)?

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?

Human infection with raccoon roundworm happens after eating the eggs of this worm passed in the feces of raccoons. Most infections happen 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
  • coma

Symptoms will develop within 1 to 4 weeks after exposure.


How can I prevent raccoon roundworm?

If raccoons are living near your home, you should carefully remove all raccoon feces and any materials contaminated with feces. Either bury or throw away these items. Take care not to contaminate your hands or clothing by wearing rubber gloves and using a shovel while removing feces. Outdoor spaces can be carefully cleaned with boiling water.

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

Cover sandboxes 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.​


How is raccoon roundworm treated?

There is no known treatment that is completely effective against the disease. Certain medications can help in some cases. Your healthcare provider will discuss your treatment options with you.

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