Diphyllobothriidae

Diphyl proglottidE

Diphyllobothriidae is a family of cestodes (tapeworms) within the order Diphyllobothriidea. Members of this family are known to infect a variety of vertebrate hosts, including humans, and are responsible for the disease known as diphyllobothriasis.

Morphology

Diphyllobothriidae tapeworms are characterized by their elongated, ribbon-like bodies, which are divided into segments called proglottids. Each proglottid contains a complete set of reproductive organs. The scolex, or head, of these tapeworms is equipped with bothria, which are slit-like grooves that allow the parasite to attach to the intestinal wall of its host.

Life Cycle

The life cycle of Diphyllobothriidae involves multiple hosts. The adult tapeworm resides in the intestines of a definitive host, which is typically a fish-eating mammal, including humans. Eggs are released into the environment through the host's feces. These eggs hatch into free-swimming larvae called coracidia, which are ingested by small crustaceans, the first intermediate hosts. The larvae then develop into procercoid larvae within the crustacean. When the crustacean is eaten by a fish, the second intermediate host, the larvae migrate to the fish's tissues and develop into plerocercoid larvae. The cycle is completed when a definitive host consumes the infected fish.

Pathogenesis

In humans, infection with Diphyllobothriidae can lead to diphyllobothriasis, which is often asymptomatic but can cause abdominal discomfort, diarrhea, vomiting, and weight loss. In severe cases, it can lead to vitamin B12 deficiency and megaloblastic anemia.

Diagnosis and Treatment

Diagnosis of diphyllobothriasis is typically made by identifying eggs or segments of the tapeworm in stool samples. Treatment usually involves the administration of antiparasitic medications such as praziquantel or niclosamide.

Prevention

Preventive measures include thoroughly cooking or freezing fish to kill any larvae present. Public health education on the risks of consuming raw or undercooked fish is also important in preventing infection.

Notable Species

Some notable species within the Diphyllobothriidae family include:

• Diphyllobothrium latum
• Diphyllobothrium nihonkaiense
• Diphyllobothrium dendriticum

Related Pages

• Cestoda
• Diphyllobothriasis
• Praziquantel
• Niclosamide
• Megaloblastic anemia