Covers the pinworm Enterobius vermicularis, its itching symptom, male and female morphology, egg features, and the stages of its lifecycle from ingestion to egg deposition on the perianal skin. It then describes the whipworm Trichuris trichiura, including trichuriasis and its effects, adult sizes, barrel-shaped brown eggs, and the soil maturation of eggs before infection and the worm's development in the colon.
Topic 53 of 64 in the MU Sofia syllabus for Biology (Dental Medicine, Year 1). The free AceMed note covers it in 2 sections, about 265 words (2 min of reading), with 14 flashcards.
In this note
Enterobius Vermicularis (Pinworm)
Trichuris Trichiura (Whipworm)
Enterobius Vermicularis (Pinworm)
General Information
Also known as pinworm.
Hosts: Humans.
Symptoms
Causes itching in the anal area, particularly intense at night.
Morphology
Males are smaller than females, adhering to typical phylum characteristics.
Eggs: Translucent, with a thick shell flattened on one side, and may contain a developing embryo or a fully formed pinworm larva up to 150µm in length.
Lifecycle
Ingestion: Eggs are ingested and hatch in the small intestine.
Development: Larvae grow rapidly and migrate to the colon, where they molt and mature into adults.
Reproduction: Males and females mate; males die shortly after mating and are expelled with the stool.
Egg Development: Females attach to the large intestine and fill with eggs.
Egg Laying: Once filled with eggs, females move towards the rectum and emerge from the anus to deposit eggs.
Egg Transmission: Eggs are deposited on perianal skin or directly into the environment via the stool, ready for ingestion to restart the cycle.
Continue reading free
The whole note, all 2 sections, is free with an AceMed account, with its 14 flashcards. Premium adds flashcard recall, highlights and Ask AI.
