Pinworms in Children: What You Should Know

Pinworms in children are characterized by the presence of parasites in the perianal area. It's very common and its treatment is simple.
Pinworms in Children: What You Should Know

Last update: 06 January, 2022

Parasitosis is common during childhood, and infantile pinworm is one of the most frequent types worldwide. In general, it affects children between the ages of 5 and 10, especially during the school months. The Spanish Association of Pediatrics estimates that 1 in 2 children acquires this infection due to the easy spread of the parasite that produces it. Below, we’ll tell you what it is, how it manifests itself, and how pinworms in children are treated. Keep reading!

What are pinworms in children?

Pinworms are an infection caused by a parasite called Enterobius vermicularis, also known as pinworm.

This microorganism enters through the mouth, by direct contact with the eggs or larvae that contaminate water or some surfaces. The infection is more common in children because they often put dirty hands in their mouths or accidentally swallow dirt or sand.

Once in the stomach, the pinworm eggs hatch, and the young larvae are released. After two to six weeks, the mature larvae reach the large intestine where they finally lodge.

During the nights, the female of this parasite comes out through the anus and lays her eggs in the perianal area. These cause an inflammatory reaction on the skin that causes intense itching.

Through scratching, the child makes contact with the eggs, which tend to adhere to the nails. And by putting their hands in their mouth again, they perpetuate the cycle of infection.

Similarly, eggs can contaminate clothing, sheets, and other inanimate objects. Unfortunately, they survive outside the human body for between 2 and 3 weeks, which makes contagion between cohabitants very likely.

We must emphasize that pinworms only infect humans and not animals.

A digital illustration of pinworms in the intestine.

How does it manifest itself in the child?

As mentioned above, the characteristic symptom of pinworms in children is great itching in the perianal area, especially at night. In addition to discomfort, this condition can bring alterations in rest and has been associated with some cases of sleepwalking.

In girls, this itching can spread to the vagina and cause vulvovaginitis. And because of the irritation from scratching, little ones may also experience pain or burning when urinating.

When the infection isn’t treated, other signs and symptoms may develop, such as the following:

  • Bruxism
  • Lack of appetite
  • Weightloss
  • Fatigue
  • Nervousness
  • Anemia

In some cases, skin lacerations may occur due to scratching, which can contribute to a bacterial superinfection of this tissue.

Diagnosing pinworms in children

In general, the diagnosis is usually straightforward, as parents detect the worm in their children’s underwear. Its appearance is very characteristic and unmistakable: It looks like a mobile white piece of thread that’s about a quarter to half an inch long.

If you fail to spot the worm itself but there are symptoms that cause you to suspect an infection, a professional may request a study such as a tape test. The objective of this is to collect the eggs from the margin of the anus with adhesive tape. To increase the chances of finding them, the sample should be taken on 3 consecutive nights. A biochemist then looks at the material under the microscope and confirms the infection.

The blood test in these cases isn’t necessary, as pinworms don’t considerably elevate eosinophilic leukocytes as other parasites do. For this reason, this type of study isn’t usually requested.

The treatment of pinworms in children

Pinworms in children are easy to treat but they can come back if proper precautions aren’t taken.

The antiparasitic of choice is mebendazole, which is indicated in two doses: First, at the time of diagnosis, and then again after 15 days. This strategy seeks to ensure that all eggs and larvae are eradicated.

A point to note is that this treatment is prescribed for all the child’s cohabitants, as they have a high probability of carrying the parasite even without symptoms.

As we’ve anticipated, reinfection by pinworms is common and it’s very important to clean the child’s clothing and personal items to avoid it. In this sense, you need to wash all clothing, sheets, and towels with boiling-hot water to eliminate the larvae and their eggs. If this isn’t possible, the textiles should be kept in a tightly closed plastic bag for a week and then washed in the usual way.

If your little one suffers from skin infections from continuous scratching, a soothing lotion should be applied to the area or an allergy reliever by mouth. And in the event that it becomes infected, the pediatrician may indicate an antibiotic cream.

Can pinworms in children be prevented?

A mother washing her daughter hands in the bathroom sink.

When there’s a pinworm infection at a daycare, it’s difficult to prevent other children from getting it. However, you can instill in your little one a series of rules such as those described below:

  • Teach your child the importance of frequent handwashing with soap and water.
  • Make a habit of this practice before each meal and after going to the bathroom.
  • Keep nails short and clean, to avoid the accumulation of microbes on them.
  • Change underwear daily.
  • Wash sheets at least 1 time a week.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.



This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.