What is the larva of Hymenolepis nana?
Hymenolepis nana is unique among tapeworms in that the adult worm develops after the egg is ingested. The hooked oncosphere then invades the intestinal mucosa and develops into a cysticeroid larva.
How many Proglottids does Hymenolepis nana have?
Adult worms average 2 cm in length and have about 200 proglottids, each containing about 150 eggs. The most distal proglottids disintegrate to release eggs into the lumen. About 20 to 30 days after initial ingestion, the worm begins to shed eggs in the stool.
Does Hymenolepis nana spread in the body?
H. nana, also known as dwarf tapeworm, is a cyclophyllidean tapeworm with embryonated eggs. It is probably the most prevalent tapeworm worldwide, and it is the only tapeworm that can be transmitted directly from human to human.
What is the most characteristic feature of Hymenolepis nana egg?
Eggs of Hymenolepis nana. These eggs are oval and smaller than those of H. diminuta, with a size range of 30 to 50 µm. On the inner membrane are two poles, from which 4-8 polar filaments spread out between the two membranes.
What is the larva of Taenia Saginata?
Larval encystment usually occurs in striated muscle and the central nervous system, and within 8 to 11 weeks the larvae, termed Cysticercus solium (cellulosae) in hogs and Cysticercus bovis in cattle, become infectious. Cysticerci are ellipsoid, translucent bladder-like cysts in which an inverted scolex has developed.
What do Ascaris eggs look like?
Ascaris lumbricoides unfertilized eggs. Fertilized eggs are are rounded and have a thick shell with an external mammillated layer that is often stained brown by bile. In some cases, the outer layer is absent (known as decorticated eggs). Fertile eggs range from 45 to 75 µm in length.
Why is Hymenolepis nana described as dwarf tapeworm?
Hymenolepiasis. Infection with the dwarf tapeworm (so-called because of its small size) Hymenolepis nana occurs worldwide, mostly in children living in conditions with poor sanitation.
How do you identify Hymenolepis nana?
Initially, the identification of hymenolepis nana was confirmed by parasitological method including direct wet-mount and formalin-ethyl acetate concentration methods. Afterward, PCR-sequencing analysis of ribosomal ITS2 fragment was targeted to investigate the molecular identification of the parasite.
What are the typical symptoms of H. nana infection?
Those who have symptoms may experience nausea, weakness, loss of appetite, diarrhea, and abdominal pain. Young children, especially those with a heavy infection, may develop a headache, itchy bottom, or have difficulty sleeping. Sometimes infection is misdiagnosed as a pinworm infection.
What is mode of transmission of Hymenolepis nana?
One becomes infected by accidentally ingesting dwarf tapeworm eggs. This can happen by ingesting fecally contaminated foods or water, by touching your mouth with contaminated fingers, or by ingesting contaminated soil.
What is larva of Taenia?
The larval stage of Taenia solium is Cysticercus cellulosae, the cause of porcine and human cysticercosis.
What is the larval stage of Taenia solium called?
cysticercus
Cysticercosis is the disease associated with the development of the larval form (cysticercus) of the pork tapeworm, Taenia solium, within an intermediate host.
What kills Ascaris eggs?
Since Ascaris eggs have 3 layers and are very resistant, the acetic acid concentration, which can be effective on these eggs are thought to be effective also on many other parasitic agents.
How do you remove Ascaris from your body?
Anthelmintic medications (drugs that remove parasitic worms from the body), such as albendazole and mebendazole, are the drugs of choice for treatment of Ascaris infections, regardless of the species of worm. Infections are generally treated for 1–3 days. The drugs are effective and appear to have few side effects.
What is the infective stage of Hymenolepis nana?
The infective eggs develop into cysticercoids that can be ingested by humans or rodents, releasing oncospheres that then penetrate the intestine and develop into cysticercoid larvae. These larvae can then attach to the intestinal mucosa and develop into adults. Eggs are passed in the stool.
What is the pathogenesis of Hymenolepis nana?
Hymenolepiasis is the most common intestinal tapeworm infection of humans caused by worm of family cestoda, genus Hymenolepis and species nana. This infection does not require an intermediate host and infection can occur directly from one infected person to another by fecal-oral transmission.
What is the treatment of Hymenolepis nana?
Treatment. Praziquantel, adults and children, 25mg/kg in a single-dose therapy.