Cestoda Lecture Notes

Flashcards about Cestoda

What is the typical dimension range of Cestoda?

Approximately 1 mm to 12-20 meters

What is the shape of Cestoda?

Ribbon-shaped and segmented

What are the three main body sections of Cestoda?

Scolex, neck, strobila

What are the fixation organs found on the scolex of some Cestoda?

Botryas, suckers, chitinized hooks

What is the neck of Cestoda?

The place of formation of segments in Cestoda

What is the body of Cestoda consisting of proglottides called?

Strobila

What are the stages of development of Cestoda?

Egg, oncosphere, finn

What is an oncosphere?

Larva with 6 hooks, covered with embryophore

What are the different types of Finns?

Cysticercus, cysticercoid, cenur, echinococcus, alveococcus, plerocercoid

What are Cysticercus?

Vesicles containing liquid and a scolex with attachment organs immersed inside

What is a cysticercoid?

Double-walled vesicle containing a scolex, a neck, and a long tail rudiment with hooks

What is a cenure?

Bubble with several heads. Each head forms a separate neck and body

What is echinococcus?

Single-chamber bubble with liquid; its inner shell forms capsules, which contain scolexes

What is Alveococcus?

Small irregularly shaped blisters connected to each other; from the outer surface of which daughter blisters are formed

What is a plerocercoid?

Primitive ribbon-shaped finna with a single head and bothria

What are Taeniasis and Cysticercosis?

Diseases resulting from infection with parasitic tapeworms belonging to Taenia species.

What tapeworms are most commonly responsible for human infection?

Taenia solium and Taenia saginata

What causes taeniasis in humans?

Infection with adult tapeworms of either T. solium or T. saginata

What causes cysticercosis?

The metacestode, or larval stage, of Taenia solium

What is Taenia saginatus?

Beef tapeworm

Where does Taenia saginatus localize in the body?

Small intestine

Who are the final hosts of Taenia saginatus?

Humans

Who are the intermediate hosts of Taenia saginatus?

Cattle, buffaloes, zebu, yaks, and some species of antelope

Where do finns develop in the intermediate host?

Connective tissue of skeletal muscles, heart muscle, tongue, and chewing muscles

What is the life expectancy of the Finns in the intermediate host?

11-12 months

What is the invasive stage for human finns?

Cysticercus

What is the path of infection for Taenia saginatus?

Alimentary

How long does it take Taenia saginatus to develop to the puberty stage?

3 months

What is the lifespan of Taenia saginatus?

Up to 15 years

How is Taenia saginatus diagnosed?

Detection of chainworm segments in faeces

What is Taenia solium?

Pork tapeworm

Where does Taenia solium localize in the body?

Small intestine

Who are the final hosts of Taenia solium?

Humans

Who are the intermediate hosts of Taenia solium?

Pigs and humans

What is the path of infection for Taenia solium?

Alimentary

What is the invasive stage of Taenia solium?

Finna (cysticercus), develops in pig muscles

How is Taenia solium diagnosed?

Detection of chainworm segments in faeces

How does human infection of Taeniasis occur?

Eating insufficiently heat-treated beef or pork containing finns

How does infection of an intermediate host occur?

Ingestion of proglottides when eating sewage

Who are the intermediate hosts in cysticercosis?

Humans

What is the invasive stage of cysticercosis?

Oncospheres, from which Finns – cysticerci develop

What are the ways of infection with cysticercosis?

Introduction of oncospheres by mouth or autoinvasion

What organs are affected by cysticercosis?

Brain, eyes, heart muscle, skeletal muscles

How is cysticercosis diagnosed?

Biopsy, X-ray, ophthalmoscopy, immunodiagnostics

What is Hymenolepis nana?

Dwarf tapeworm

Where does Hymenolepis nana localize in the body?

Small intestine

Who are the final and intermediate hosts of Hymenolepis nana?

Humans

What are the ways of infection for Hymenolepis nana?

Per os (alimentary, contact), autoinvasion, re-invasion, accidental ingestion of intermediate hosts

What are the features of parasitization for Hymenolepis nana?

A large number of parasites, Frequent change of attachment location, Severe intestinal injury, Auto- and re-invasion, Rapid spread of the disease

What are the symptoms of Hymenolepis nana infection?

Abdominal pain, decreased appetite, nausea, unstable stools, malaise, weakness, fatigue, irritability, headache, dizziness, seizures, fainting, memory impairment, insomnia

How is Hymenolepis nana diagnosed?

Detection of eggs in faeces