Best practices for nuisance wildlife control operators in New York State

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Ch 4: Section four: What you need to know about wildlife diseases

Raccoon roundworm

Caused by: A parasite.

Most common way people catch it: "Dirty" hand touches mouth. Put contaminated object directly into mouth.

Worst-case scenario: Death.

How common in the Northeast? Although the worm is common in raccoons, few people contract the disease.

Most vulnerable groups: Young children.

This disease is caused by a parasite, a roundworm called Baylisascaris procyonis. The roundworm larvae cause problems as they travel through the person's muscles and various organs, including the liver, brain, lungs, and eyes. The severity of the infection depends on how many of the parasite's eggs were ingested, and where the larvae migrate. Although serious infections are rare, raccoon roundworm can be fatal in people.

Raccoons are the primary host of this roundworm, which is commonly found in their small intestines. The parasite has also been found in mice, squirrels, rabbits, birds, woodchucks, and dogs.

How do you catch it?

Raccoons shed millions of the microscopic roundworm eggs in their feces. It takes about a month for newly deposited eggs to develop to the infective stage. The eggs can only develop into worms when they're in an animal's body, but the eggs are hardy and may survive for years in soil, sand, or water.

People may encounter the eggs through direct contact with raccoon droppings or by touching a contaminated area or object. If they don't wash their hands, they may later transfer the eggs to their mouths. Small children are particularly vulnerable because they tend to put their hands, and other objects such as bark, wood chips, toys, soil, or even droppings, into their mouths.

Other animals may become infected by eating an infected animal or through contact with the feces of an infected animal.

Symptoms

Symptoms in people may include nausea, skin irritations, tiredness, liver enlargement, loss of coordination and muscle control, blindness, inattentiveness, and coma.

Raccoons rarely show symptoms of the disease but the species that don't usually play host to this worm (such as woodchucks, squirrels, birds) tend to show abnormal behaviors when infested. They'll tilt their heads and have difficulty walking or climbing. They may lose their fear of people, circle, roll on the ground, fall over, lay on their sides and paddle their feet, or fall into a coma.

Treatment

If someone's been exposed, or even suspects exposure to raccoon roundworm, seek immediate medical care. If the worms can be killed before they migrate through the body, there's a very good chance that the disease will be prevented. But if the condition is not treated early, recovery is less assured. Raccoon roundworm infections are very difficult to diagnose in people.

Protection on the job

If you're working in an area that's contaminated with raccoon feces, wear a proper respirator, rubber gloves, rubber boots, and disposable coveralls. Because the eggs are resistant to common disinfectants, the feces and any contaminated materials should be burned. If that's not feasible, double-bag the materials and bury them deeply.

Contaminated clothing can be double-bagged and discarded, or washed in boiling water with bleach. Scrub rubber boots with bleach and a scrub brush. Clean traps before storing, to remove feces while they are fresh. Traps and other equipment that can withstand the heat can be flamed. If that's impractical, clean with boiling water and bleach.

Advice for customers

1. Have your pets "wormed" three to four times each year.
    
2. To prevent your children from encountering roundworm eggs, keep them away from areas that are frequented by raccoons. Cover their sandboxes. Train them to wash their hands and scrub their fingernails after playing outdoors, especially if they were in your garden or the sandbox.
    
3. Discourage raccoons from living in and around your home (management techniques are discussed in Appendix B).
    
4. Prompt removal and destruction of raccoon feces will reduce the risk of human exposure. Raccoons typically defecate at the base of trees, on fallen logs, on large rocks, and wood piles, and in barns or other outbuildings. Raccoon feces may also be found in children's sandboxes, attics, fireplaces, garages, decks, rooftops, haylofts, and compost piles.
    
5. Areas of soil or concrete are best decontaminated by a thorough flaming using a handheld propane torch (weed burner). Wooden decks and patios can be cleaned with boiling water. Soil can be turned over with a rake or shovel, then flamed. Repeat this process several times. To decontaminate a fireplace or woodstove and chimney, build a roaring fire.

For more information about raccoon roundworm

• CDC Parasitic Disease Information - Raccoon Roundworm Infection Fact Sheet
   
• Michigan Department of Natural Resources - Raccoon Roundworm (Baylisascaris)

Review questions

1. You can see from the outside if a raccoon is infested with Baylisascaris roundworms. (Circle correct answer)
   true false
    
2. Young children are most vulnerable to this disease because
   1. they're more likely to put contaminated objects and their hands into their mouths
   2. they have small bodies, so the worms reach their brains faster
   3. raccoons prefer them
   4. their immune systems haven't been exposed to the disease yet
       
3. There were many raccoons living in your customer's backyard. They want to know how to clean up so their kids can play outdoors again. You tell them
   1. forget it, and buy them a computer game
   2. clean the deck with boiling water. Soil should be raked and flamed repeatedly. Replace the sand in the sandbox. Build a roaring fire to clean out the fireplace, stove, and chimney.
   3. don't worry, the rain will take care of it
   4. those full body protection "bunny suits" are very fashionable—remember the computer commercials?

Answers

1. false
    
2. a
    
3. b

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