Enterobius vermicularis (pinworm)

Definition

Enterobius vermicularis, commonly known as pinworm, is a small, white nematode that primarily infects the intestines of humans, particularly children. It is the most common human intestinal helminth and is notorious for causing itching and discomfort around the anal region, which is often the first noticeable symptom of infection.

5 Must Know Facts For Your Next Test

1. Pinworm infections are highly contagious and can spread easily through contaminated surfaces or direct contact with infected individuals.
2. Infection is often asymptomatic, but when symptoms do occur, they typically include intense itching, especially at night.
3. The lifecycle of Enterobius vermicularis involves adults living in the host's intestines and females laying eggs around the anus at night.
4. Diagnosis can be made using the 'tape test', where a piece of tape is applied to the anal area to collect eggs for examination under a microscope.
5. Treatment usually involves oral medications such as mebendazole or albendazole, and it's essential to treat all household members to prevent reinfection.

Review Questions

• What are the primary symptoms of an Enterobius vermicularis infection, and how do they manifest in affected individuals?
  • The primary symptoms of Enterobius vermicularis infection include intense itching around the anal area, especially at night when female pinworms lay their eggs. This itching can lead to irritability and sleep disturbances in affected individuals. In some cases, secondary bacterial infections may occur due to scratching the affected area. Some individuals may experience abdominal discomfort, but many infections can be asymptomatic.
• Discuss the lifecycle of Enterobius vermicularis and how it contributes to its transmission among individuals.
  • The lifecycle of Enterobius vermicularis begins when a person ingests pinworm eggs, which can occur through contaminated hands or surfaces. Once ingested, the eggs hatch in the intestines, where adult worms mature and reside. Female pinworms migrate to the anal region at night to lay their eggs, causing pruritus ani. This itching leads to scratching and can transfer eggs back onto hands or surfaces, facilitating easy transmission to others. As a result, outbreaks are common in settings like schools and daycare centers.
• Evaluate the effectiveness of treatment options for pinworm infections and discuss any necessary preventive measures that should be taken to reduce recurrence.
  • Treatment for pinworm infections typically involves oral medications like mebendazole or albendazole, which effectively eliminate adult worms and their eggs. However, to ensure complete eradication of the infection and prevent recurrence, it is crucial to treat all household members simultaneously. Preventive measures include maintaining strict personal hygiene practices such as regular handwashing, keeping nails trimmed short, and daily washing of bedding and clothes. Education on transmission routes is also vital to reduce outbreaks in communal settings.

Related terms

Nematodes: A diverse group of unsegmented roundworms that include many species, some of which are parasitic.

Ova: The eggs laid by pinworms, which are responsible for spreading the infection when ingested.

Pruritus ani: A medical term for itching around the anus, which is a hallmark symptom of pinworm infection.