Tapeworms are parasites that live in the small intestines of many species, including humans.
Depending on the tapeworm species, their length may vary from 1 cm to 10 meters in length. Other than the tapeworm head, their body consists of small segments called proglottids. These are egg sacs that break off the tail of the tapeworm. Both the eggs and proglottids are released in animal feces. Of all the tapeworms our pets may carry, the Echionococcus sp pose the most disease risk in people.
Different Tapeworms Species
These are the most common tapeworms found in our dogs and cats in North America. Their eggs are passed in animal feces, but their eggs cannot infect other animals or people. The eggs must be eaten by flea larvae and then they will develop into an infective stage in the adult flea. Cats and dogs become infected when they swallow the adult flea. Flea control is an important control measure to prevent your pet developing Dipylidium. Generally, D. Caninum does not cause illness in our pets, but in large numbers they may cause your pet to vomit up worms, to lose weight or more commonly they may cause your pet to have an itchy anal region from the mobile proglottids.
Most human infections are from livestock and not our pets. People become infected when they eat animal muscle or organs that contain Taenia cysts. Similarly, pets may become infected when they eat uncooked meat or infected small wild animals such as mice, rabbits and voles. T. pisiformis is commonly found in dogs and T. taeniae formis is found in cats.
These are the smallest of the tapeworms but they will cause the most significant disease in humans. EIchinococcus eggs are unlike other tapeworm eggs and they do not require fleas or other animals to develop and become infective. This means the eggs in the feces are already capable of causing disease. They exist in wild canids such as foxes and small prey species. They may also infect domestic dogs and less commonly domestic cats. They rarely cause disease in cats or dogs. Humans, however, are accidental hosts and can have large damaging cysts develop in their bodies.
DIagnosis and Prevention of Tapeworms
Eastern Shore Veterinary clinic can preform an annual fecal float to detect tapeworm and other parasite eggs. Eggs may only be shed intermittently and in low numbers, so a single negative float cannot rule out infestations.
Contact us if you notice proglottids on your pet. They may appear similar to grains of rice or sesame seeds near your pet’s anal region.
Intact proglottids cannot be used to determine the species of tapeworms.
Prevention is multi stepped.
1. regular deworming of all your pets – monthly for all outdoor pets is recommended
2. prevent your outdoor pets from hunting and scavenging
3. ensure all meat and animal based products fed to your pets are properly cooked
4. promptly pick up your pet’s feces
5. wear gloves when working in soil
6. always thoroughly wash your hands after handling raw meat, feces, or soil
7. prevent reinfection – our pets may shed high numbers of parasite eggs for a few days after deworming so be very diligent in removing feces and washing your hands
8. monthly flea prevention is also important
Written by: Dr. Cindy Rodgerson DVM