Introduction

Classification

Taxonomy

• Class: Cestoda.
• Family: Dilepididae.
• Genus: Dipylidium.

Active Forms

Resting Forms

Clinical Effects

Epidemiology

Habitat

• Adult tapeworm in the small intestine of the dog, other Canidae, Felidae, and rarely children.
• Segments and eggs in the environment, particularly in areas where the dog sleeps.
• Metacestode (cysticercoid) in the body cavity of the flea, primarily Ctenocephalides felis, and chewing louse, Trichodectes canis.

Lifecycle

• See lifecycle diagram  :
  • Adult tapeworm.
  • Gravid proglottid.
  • Egg.
  • Cysticercoid.

Transmission

Transmission to flea/louse

• Segments migrate out of anus and around perianal area. Can be eaten by chewing lice in this area.
• Segments fall to the ground, particularly where the dog spends time resting.
• Flea eggs also fall off the dog to the ground in these areas .
• Flea larvae attracted to eat segment as a source of protein.

Transmission to dog

• Infected adult flea parasitises dog.
• Dog accidentally ingests the adult flea or louse containing a cysticercoid when grooming itself.
• Some dogs may show hypersensitivity to flea bites which will result in increased grooming and thus increase the likelihood of ingesting a flea.

Pathological effects

• Not known.
• Little protective immunity develops in the dog.
• Some flea species, eg Ctenocephalides canis, or at the least some strains of it, destroy most cysticercoids by a hemocyte (cellular) and humoral response.
• No 'immunity' appears to develop in Ctenocephalides felis.

• The presence of 1 or many tapeworms, even several hundred, usually has little effect on the health of a well-fed dog.
• Irritation of a segment spontaneously migrating from the anus can cause 'scooting'.
• Dog infected with D. caninum will concurrently be infected with fleas or lice and is likely to show pruritus associated with the hypersensitivity response to the ectoparasites.
• Large numbers of worms could reduce growth rates in young, poorly nourished dog - rare .
• Very rarely, obstruction of the intestine from many hundreds of worms can occur.

Control

Control via animal

• Anthelmintic treatment of dog.
• Treat dog for fleas Ctenocephalides felis or lice Trichodectes canis.

Control via chemotherapies

Control via environment

• Control fleas Ctenocephalides felis.

Diagnosis

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Boreham R E & Boreham P F L (1990) Dipylidium caninum: life cycle, epizootiology, and control. Comp Cont Educ Pract Vet 12 (5), 667-675 VetMedResource.