Cestoda - Tapeworms

Tapeworms live in the gastrointestinal tract feeding on the passing food. The most common tapeworm species in humans are fish, dwarf, beef and pork tapeworms. Fish, beef and pork tapeworms grow many meters long. Dwarf tapeworms can only reach a length of a few centimeters.

A tapeworm attaches to the intestinal wall with its head, scolex. Depending on the tapeworm species the scolex usually has a set of hooks and four suckers. Hooks dig into the mucosa.

The neck produces segments called proglottids which make up the body and tail. Each segment has both male and female reproductive organs. Segments can produce eggs on their own but sometimes mate with other segments or even other tapeworms. Segments absorb nutrients through their skin and have the ability to produce eggs. Over time the segments fill with eggs and detach from the tail. They are then carried out of the body in the feces.

The intermediate host ingests tapeworm eggs with grass or other food infected with the human feces. In the gut microscopic larvae hatch from the eggs. They then penetrate the intestinal wall, enter the bloodstream and travel to muscles or other body parts. There they encyst into shell structures which are the resting forms of tapeworms. For example, Taenia solium cysticerci larvae are deposited in infected pig muscles. If you do not cook the pork meat the larval cysts excyst in your small intestine. They will attach to the intestinal mucosa and develop into adult pork tapeworms.

• Diphyllobothrium Latum - Fish Tapeworm
  
  Diphyllobothrium latum (fish tapeworm) life cycle, symptoms, diagnosis and treatment as well as pictures and videos. It uses fish as an intermediate host and causes a parasitic infection called diphyllobothriasis.
• Hymenolepis Nana - Dwarf Tapeworm
  
  Hymenolepis nana (dwarf tapeworm) life cycle, symptoms, diagnosis, treatment and pictures. Hymenolepiasis is a parasitic disease.
• Taenia Saginata - Beef Tapeworm
  
  Beef tapeworm (Taenia saginata) life cycle, symptoms, diagnosis and treatment (pictures included). Beef tapeworm causes taeniasis (parasitic disease).
• Taenia Solium - Pork Tapeworm
  
  Taenia solium (pork tapeworm) causes taeniasis and cysticercosis. Find information such as life cycle, symptoms, diagnosis and treatment as well as pictures and videos.