Dipylidium Infection
(DI-pih-LID-ee-um)
Dog and Cat Flea Tapeworm
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The most common tapeworm of dogs and cats in the United States is called Dipylidium caninum (DIE-pih-LID-ee-um K-nine-um). Infection is common and found throughout the world.
By swallowing a flea infected with a tapeworm larvae. A dog or cat may swallow a flea while self-grooming. Once the flea is digested inside the dog or cat, the larval tapeworm is free to develop into an adult tapeworm.
The adult tapeworm is made up of many small segments, called proglottids (pro-GLOT-ids), each about the size of a grain of rice; adult tapeworms may measure 4-28 inches in length. As the tapeworm matures inside the intestines, these segments (proglottids) break off and pass into the stool.
Although cats and dogs are rarely ill as a result of a Dipylidium tapeworm infection, the proglottids can sometimes be seen crawling near the anus or on the surface of a fresh bowel movement. Proglottids contain tapeworm eggs; these eggs are released into the environment when the proglottid dries out. The dried proglottids are small (about 2 mm), hard and yellowish in color and can sometimes be seen stuck to the hair around the pet's anus.
Tapeworms are not usually harmful to your pet. Weight loss may occur if your pet is heavily infected. Sometimes, an infected dog will "scoot" or drag its anus across the ground or carpet because the segments are irritating to the skin in this area.
Occasionally, a portion of this tapeworm will be passed when the dog vomits. If this happens, a worm several inches in length may be seen.
Tapeworm infection is usually diagnosed when the moving segments are seen crawling around the anus or in a bowel movement. Dipylidium tapeworm eggs are rarely released into the feces and are therefore not usually detected by routine fecal exams performed by your veterinarian. Because of this, veterinarians depend on you to notify them of possible tapeworm infection in your pet.
Yes. For a person to become infected with Dipylidium, he or she must accidentally swallow an infected flea. Most reported cases involve children. The risk of infection with this tapeworm in humans is low. The most effective way to prevent infections in pets and humans is through flea control. A child who is infected will usually pass proglottids (or what appears as rice) in a bowel movement or find them stuck to the skin around the anal area.
Treatment for both animals and humans is simple and very effective. A prescription drug called praziquantel is given, either orally or by injection (pets only). The medication causes the tapeworm to dissolve within the intestines. Since the worm is usually digested before it passes, it may not be visible in your dog's stool. The drugs are generally well-tolerated.
See your health care provider for diagnosis and treatment.
- Control fleas on your pet, and in their indoor and outdoor environments.
- Have your veterinarian treat your dogs and cats promptly if they have tapeworms.
- Clean up after your pet, especially in playgrounds and public parks. Bury the feces, or place it in a plastic bag and then put it in the trash.
- Do not allow children to play in areas that are soiled with pet or other animal feces.
- Teach children to always wash their hands after playing with dogs and cats, and after playing outdoors.
This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have a parasitic infection, consult a health care provider.
Dipylidium Infection
