ENTEROBIUS VERMICULARIS

· Endoparasite of the large intestine (ileocaecal region), caecum, colon, and vermiform appendix, especially in children (only in humans).

Adhering to the mucosa, the worms feed on bacteria and epithelial cells.

· Sexes are separate with distinct sexual dimorphism. Single penial seta is present in males.
· Simple and monogenetic life cycle, females migrate out through the colon and rectum and deposit an enormous number of eggs in the skin folds of the anus and cause intense itching. When skin about the anus is scratched, eggs are picked upon fingers and under nails from where they find their way to food and are swallowed.

They hatch in the stomach and the juveniles migrate to the colon and develop into adult worms.

The life cycle completes in 2-4 weeks.

· Infection occurs through contaminated food and water. Auto infection occurs by scratching (itching), Retroinfection (entry of larva or adult to the rectum or anti direction of the digestive tract)
· Males die after copulation.
· Total moulting occurs four times to become an adult.
· An embryonated egg (2nd stage) is the infective stage.
· Causes enterobiasis or Oxyuriasis
· Pinworms are not highly pathogenic, the main symptoms are intense itching of the anus, inflammation of the mucous membrane of the infected regions (colon and appendix), loss of appetite, insomnia, abdominal pain, diarrhoea, nausea, intestinal haemorrhage, hysteria, and restlessness.

Also, Read our Other Notes Important for Entrance Exams:

• Phylum Protozoa
• Leishmania donovani
• Amoeba proteus
• Phylum Porifera
• Phylum Coelenterata
• Hydra
• Phylum Ctenophora
• Phylum Platyhelminthes
• Liver fluke
• Tapeworm
• Phylum Nemathelminthes
• Ascaris lumbricoides (Roundworm)
• Wucheria bancrofti (Filarial worm)
• Ancylostoma (Hookworm)
• Enterobius (Pinworm)
• Phylum Annelida
• Earthworm
• Phylum Arthropoda
• Cockroach
• Mosquito
• Phylum Mollusca
• Phylum Echinodermata
• Phylum Chordata