How to prevent and treat pinworm infection in kids
When parents first notice their kids have a pinworm infection, they usually flip.
“It freaks parents out,” says Dr. Kristin Bencik-Boudreau, a pediatrician at Bayshore Pediatrics, a primary care practice of Children's Hospital of Wisconsin in Glendale, Wisconsin. The reason for this – fair warning – is frightful and disgusting.
“They usually see little white threads in the [child’s] poop, and the kids are complaining of anal itching,” Bencik-Boudreau says. The “threads” are pinworms – also called threadworms – which are intestinal parasites. And calls from freaked out parents usually come in the middle of the night, Bencik-Boudreau says.
It’s at night when the roughly half inch-long female pinworm leaves the intestinal tract and lays her eggs on the skin around the anus. “She can lay thousands of eggs,” says Dr. Bobbi Pritt, a pathologist and microbiologist subspecializing in parasites, or a parasitologist, at Mayo Clinic in Rochester, Minnesota. They get laid down with a glue that the female secretes. “That glue is really itchy – it makes people want to scratch,” Pritt says.
An itchy bottom is the most common sign of a pinworm infection. There’s even a technical term for it: “nocturnal pruritis ani; so nocturnal – it usually happens at night or in the early morning, pruritis just means itching, and ani is anus,” Pritt explains. The itchiness is not only annoying, but integral to the spread of the parasite. Especially where very young children scratch the actual skin surface (rather than through clothing), they can get the highly infectious eggs on their hands, as well as on clothes, bedsheets and toys, and family and others in the household can become infected.
Pinworm is the most common worm infection in the U.S., and up to half of kids can become infected at some time, according to the Centers for Disease Control and Prevention. We are the only hosts for the pinworm. (Pets, for example, don’t get pinworm infections from their owners or vice versa.) Adults – particularly people living in close quarters, including adults who are institutionalized – can also become infected. Experts say very young kids just tend to be especially susceptible, since they are naturally inclined to put their hands and everything they handle in their mouths.
Fortunately – though sickeningly scary for some parents initially – the infection is generally just a temporary annoyance for human hosts.
“A lot of people aren’t even symptomatic,” Pritt says. “Many people may be infected and not even know it. If they do have symptoms, the itchy bottom would be the most likely.” A typical, minor pinworm infection may be several worms (or as few as one mating pair of pinworms), while a heavy infection could involve hundreds of worms. “If it’s a heavy infection, then the child may actually have disturbed sleep,” Pritt says. “Those are pretty much the main symptoms.”
Because it can cause a lot of discomfort, kids with a pinworm infection may scratch a lot; if kids scratch the already irritated skin surface too much or too hard, it can cause the skin to break down. That can allow bacteria that we all have in our skin to come in and cause a secondary infection around the anus, Bencik-Boudreau says. “That would actually require antibiotic treatment,” she says.
In rare cases, a pinworm can crawl out of the large intestine where pinworms normally live and into the appendix or the genital tract. “This can cause appendicitis – intense abdominal pain, fever and possibly rupture [of] the appendix. Even death can occur if surgery is not immediately performed to remove the appendix,” Pritt says. She adds that the female worm can enter the female genital tract and crawl into the vagina and uterus, and get lodged in the fallopian tubes. “This can result in extreme pain and swelling in this area, fever, abscess (pus) formation, and it can even be fatal if not treated,” she says.
However, experts emphasize how exceedingly unlikely such complications are. Instead, in the vast majority of cases, the infection poses no threat at all. But even the annoyance alone, not to mention the scary gross nature of a pinworm infection, is enough to warrant clinicians recommending prevention and treatment.
Though the microscopic pinworm eggs can go airborne, they’re usually ingested when a person gets them, unknowingly, on their hands and ingests the eggs. “So it’s all about handwashing after going to the bathroom or changing diapers,” says Dr. LeAnne Kridelbaugh, president and chief medical officer of Children’s Health Pediatric Group in Dallas. In addition to thoroughly washing hands – and making sure kids do the same, especially before eating – experts advise thoroughly washing a child’s clothes and linens as well as regularly cleaning toys and surfaces. Experts say hygiene, in general, is a good way to reduce the spread of pinworm infections.
Pritt stresses, however, that given how common pinworm infections are, there’s no way to completely prevent all infections – so parents shouldn’t be blamed when they occur in kids. Rather, it’s about decreasing the likelihood of developing or spreading a pinworm infection, as much as possible.
That includes calling a child’s doctor right away if an infection is suspected. Clinicians can check to see if the child is, in fact, infected with pinworms. Medicine to treat pinworm infections is available over the counter – look for pyrantel pamoate, which is used, for example, in Reese’s Pinworm medicine – and by prescription, with clinicians frequently recommending mebendazole.
Treatment, whether prescription or OTC, involves taking one tablet, and then two weeks later taking another. “Though the medicine’s almost 100 percent effective in killing the worms, you have eggs – and it doesn’t kill the eggs, which will then hatch,” Bencik-Boudreau says. “So that’s why you repeat the treatment in two weeks.” This is important to prevent so-called autoinfections, when a person – often a child – is infected again by ingesting pinworm eggs that were on their person. Doctors recommend the whole family – or household – gets treated to prevent kids and adults from being reinfected with pinworms after they’ve cleared their own infections. Clinicians say the medications are well-tolerated. Side effects are typically minor, ranging from stomach upset for mebendazole to headache for pyrantel pamoate.
“It’s easily treated,” Bencik-Boudreau reassures parents. Experts reiterate that though potentially frightful, a pinworm infection poses little danger and can be addressed quickly.