Hymenolepis nana is the most common tapeworm in humans. It is also known as the dwarf tapeworm.Symptoms are often absent, but abdominal discomfort, bloating, or changes in bowel habits may be present. The dwarf tapeworm Hymenolepis nana is found in most warm regions of the world(Russia, and the former Soviet republics).
Hymenolepiasis is usually treated with a prescription drug called praziquantel which causes the tapeworm (both adults and larvae) to dissolve. A single dose of praziquantel has an efficacy of 96 %. Scientists at the Centers for Disease Control and Prevention have discovered cancer cells originating in a common tapeworm may take root in people with weakened immune systems, causing cancer-like tumors.