Echinococcosis is a parasitic disease caused by infection with tiny tapeworms. Echinococcosis is classified as either cystic echinococcosis or alveolar echinococcosis. Each species causes different symptoms and spreads in different ways. This information focuses on alveolar echinococcosis.
What is
Echinococcus multilocularis?
Echinococcus multilocularis is a tapeworm that lives in coyotes, foxes, and sometimes dogs and cats. It is spread in the environment by the feces (poop) of infected animals. It causes alveolar echinococcosis.
How is tapeworm spread in the environment?
The tapeworm has a complex life cycle that involves coyotes, foxes, and the rodents they eat (like mice and voles). Sometimes dogs and, rarely, cats can become infected by hunting and eating rodents.
The tapeworm's eggs are spread in the environment by the feces of infected coyotes, foxes, dogs, and cats. The eggs can live in the environment for up to a year. When rodents eat the eggs in the environment, the rodents can then be infected.
When coyotes, foxes, dogs, or cats eat an infected rodent, the larvae grow into the adult tapeworms in the animal's intestine. The adult tapeworms make new eggs. These leave the animal in their feces, starting the lifecycle all over again.
Adult tapeworms do not cause any symptoms or health problems in the coyote, fox, dog, or cat.
What is alveolar echinococcosis (AE)?
People can be infected by tapeworm by accidentally swallowing tapeworm eggs from contaminated food or water, or from handling infected animals. This can cause a rare disease called alveolar echinococcosis (AE).
What is the risk in Alberta?
The risk of people getting AE in Alberta is very low. Since 2013, there have been a small number of reported cases in the province.
Research in Alberta has shown that coyotes and foxes can have tapeworm. They often live close to houses and parks, which can put people and their pets at higher risk of exposure to this tapeworm. But even in places in North America where the tapeworm is common in animals, it’s rare that people get it.
How can people get AE?
AE does not spread person-to-person. Although it is not known how most people with AE became infected, the most common ways of getting AE appear to be:
- Eating foods (usually wild berries and herbs) or drinking water that has been contaminated with the feces of an infected coyote, fox, dog, or cat.
- Touching, petting, or handling a household pet infected with the tapeworm, then accidentally swallowing the tapeworm eggs by touching your mouth. Infected pets can have tapeworm eggs in their feces and their fur may be contaminated.
- Handling animals like coyotes, foxes, or dogs as part of your job or hobby (for example, if you are a trapper, veterinarian, or veterinary technician).
What are the symptoms?
When a person accidentally swallows the tapeworm eggs, they may not have any symptoms for the next 5 to 15 years. However, over time, this person may develop symptoms from cysts that have formed in their organs, most often in their liver. When symptoms appear, they may include:
- pain or discomfort in the upper belly
- weakness
- weight loss
- symptoms that may look like liver cancer or liver disease
How is AE treated?
AE is complicated to treat and can cause death if not treated. Surgery is the most common treatment for AE. After surgery, you may need medicine to keep the cyst from growing back.
How can people prevent AE?
The best ways to prevent AE are to:
- Practise good hand hygiene. Always wash your hands with soap and water after touching pets and before touching food. Teach children that hand washing is important.
- Wash or cook wild picked foods such as berries and herbs carefully before eating them.
- Talk to your veterinarian about ways to prevent tapeworm infection in your pets, including for information on an appropriate deworming strategy for your pet.
- Do not allow your pets to eat rodents or other wild animals.
- Keep your pet clean. Some dogs will roll in wild animal feces and can then spread tapeworm eggs from their fur to your home environment.
- Do not encourage wild animals to come close to your home.
- Do not keep wild animals as pets.
- Wear disposable gloves if you are handling a coyote, fox, or other wild animal (dead or alive).
For more information on tapeworm, AE and cystic echinococcosis see:
