Baylisascaris is more commonly known as the raccoon roundworm and is capable of infecting humans and other animals as well. When a raccoon is infected with adult roundworms, it is shedding millions of eggs into the environment in its feces. The eggs released in the raccoon feces take 2-4 weeks to become infective and can survive in the environment for years. Roundworms are species-specific in that they require a specific host to reproduce, but they are still capable of infecting a variety of other paratenic hosts. The life cycle of Baylisascaris larvae within paratenic hosts is what makes it more dangerous than other roundworms, such as Toxocara canis, the canine roundworm.
-
Baylisascaris Larvae in Humans
-
After a human ingests Baylisascaris eggs from the environment, the eggs hatch into larvae. The larvae work their way through intestinal lining into the bloodstream and travel throughout the body to affect the organs and muscles. When the larvae attempt to make a home, the body attempts to isolate and destroy it, causing damage to its own tissues. The larva most commonly seek out the liver, eyes, brain or spinal cord.
Likelihood of Infection
-
Baylisascaris is fairly common in raccoons and is most common in the Midwest, Pacific Northwest, West Coast, Northeast and Middle Atlantic. Infection in humans is rarely diagnosed. According to the CDC, in 2003 25 cases were diagnosed, resulting in only 5 deaths. Infection in other animals is more likely than in humans since animals may prey on other infected animals.
Symptoms
-
The symptoms of a Baylisascaris infection in humans depend on the amount of eggs ingested and where the larvae travel to in the body. The symptoms may take several days to weeks to appear. According to the CDC the main symptoms are nausea, tiredness, liver enlargement, loss of coordination, lack of attention to people and surroundings, loss of muscle control, coma and blindness. Symptoms are similar in both animals (except raccoons) and humans.
Treatment
-
Treatment for Baylisascaris is difficult because the migrating larvae cannot be targeted after they have left the intestines. Deworming medications do not work outside of the GI tract. If you believe you have ingested raccoon feces you should seek immediate medical attention.
Prevention
-
Preventing Baylisascaris infection is best done by avoiding contact with raccoons and their feces. Never keep raccoons as pets and do not feed them. Raccoons are wild animals and can be dangerous. Identify and avoid locations in your yard that may attract raccoons, such as sand boxes or ponds, and keep garbage well sealed. Avoid areas that may be contaminated with raccoon feces, and learn to recognize their appearance. Raccoon feces is typically dark, tubular and very pungent.
-