How is Hymenolepis transmitted?
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 infective stage of hymenolepis Diminuta?
Hymenolepis diminuta is a cestode of rodents infrequently seen in humans and frequently found in rodents. Eggs of Hymenolepis nana are immediately infective when passed with the stool and cannot survive more than 10 days in the external environment .
What’s a potential intermediate host of hymenolepis Diminuta?
diminuta. The intermediate hosts are the coprophilic arthropods (fleas, lepidoptera, and coleoptera). As the definitive host (rats) eats an infected arthropod, cysticercoids present in the body cavity transform into the adult worm. The resulting eggs are then passed through the stool.
What is the infective form of Hymenolepis nana?
The cestode, Hymenolepis nana, also called the dwarf tapeworm, causes hymenolepiasis, which is usually asymptomatic. Some weakness, headache, anorexia, and abdominal pain may occur. When passed in the stool, the eggs are infective and are ingested by beetles or flies, which serve as intermediary hosts.
Is hymenolepis Diminuta zoonotic?
Hymenolepis diminuta is a zoonotic cestode parasitizing the small intestine of rodents (definitive hosts). Humans can accidentally enter into the life cycle of this tapeworm via the ingestion of infected insects (intermediate hosts) containing cestode cysticercoids in their body cavity.
What type of organism is Hymenolepis nana?
Hymenolepiasis is primarily caused by the cestode (tapeworm) species, Hymenolepis nana (the dwarf tapeworm, adults measuring 15 to 40 mm in length).
Does Hymenolepis nana spread?
H. nana infections are much more common than H. diminuta infections in humans because, in addition to being spread by insects, the disease can be spread directly from person to person by eggs in feces.
What is the pathophysiology of Hymenolepis diminuta?
Eggs of Hymenolepis diminuta are passed out in the feces of the infected definitive host (rodents, man) . The mature eggs are ingested by an intermediate host (various arthropod adults or larvae) , and oncospheres are released from the eggs and penetrate the intestinal wall of the host , which develop into cysticercoid larvae.
How does Hymenolepis nana infect humans?
Transmission of Hymenolepis spp. Humans and other animals become infected when they intentionally or unintentionally eat material contaminated by insects. H. nanais the only cestode that parasitizes humans without requiring an intermediate host.
What is the intermediate host of Hymenolepis spp?
Arthropods, especially beetles, serve as intermediate hosts for Hymenolepis spp. The arthropod intermediate host is required for H. diminuta, but not H. nana, and humans can become infected with the latter by direct ingestion of eggs.
What is the lifespan of Hymenolepis nana eggs?
Hymenolepis nana. Eggs of Hymenolepis nana are immediately infective when passed with the stool and cannot survive more than 10 days in the external environment . When eggs are ingested by an arthropod intermediate host (various species of beetles and fleas may serve as intermediate hosts), they develop into cysticercoids,…