Hymenolepis infection or infection with the dwarf tapeworm is found worldwide. It is most often seen in children in countries in which sanitation and hygiene are inadequate. Although the dwarf tapeworm infection rarely causes symptoms, it can be misdiagnosed for pinworm infection.

Image: Left: H. nana egg in an unstained wet mount. Center: Three adult specimens of H. nana. Right: Scolex of H. nana in an unstained wet mount of stool under high magnification. Credit: DPDx, Georgia Department of Public Health, Dr. David Bruckner