Hymenolepiasis

Alternative names:

dwarf tapeworm infection; rat tapeworm; tapeworm - infection

Definition:

The infestation by one of two species of tapeworm: Hymenolepis nana or Hymenolepis diminuta.

Causes, incidence, and risk factors:

Hymenolepis live in warm climates and are common in the southern United States. H. diminuta has a larval form that lives in insects. H. nana lives in human stools. Infection rates in the United States may approach 3%.

Neither infection causes significant symptoms unless a child is heavily infested.