Ascariasis is the name of an infection caused by the roundworm Ascaris lumbricoides. When a worm lives inside the human body, the condition is called a parasitic infection.

Roundworms can live inside the small intestine for up to two years. The worms are about as thick as a pencil and can grow to be about 13 inches long. They also reproduce quickly. Female roundworms may lay more than 200,000 eggs every day; these eggs leave the body through  bowel movements.

Ascariasis is the most common type of worm infection in the world, but it is rare in the U.S. Roundworms live in the soil and in contaminated feces or bowel movements. In countries where people live in poverty, where there is poor disposal of human feces, or where crops are fertilized with human feces, Ascaris eggs can be ingested and the infection can spread from person to person via infected feces.

Children are more likely to be infected because they are more likely to put their contaminated fingers in their mouths. Once they are infected, they are more likely to have symptoms because their intestines are smaller and the worms have less room.

Your child may be at risk for roundworms if he or she has been adopted from a developing country or if you have traveled to areas of the world where these infections are common. Ascariasis tends to be more common in warm, wet, tropical countries.

Preventing roundworms

Here are preventive steps for a roundworm infection:

  • Be aware of the risk when traveling in developing countries where soil may be contaminated by feces.

  • Wash and peel or thoroughly cook fruits and vegetables before eating.

  • Wash your hands and teach your children to wash their hands with soap and water after being outside, before handling food, and after going to the bathroom.

Symptoms of roundworms in children

If your child were to swallow a roundworm egg, it would pass down into your child's intestine and hatch into a baby worm called a larva. Larvae can pass through the intestine wall into the bloodstream and travel through the lungs up into the throat. They are then swallowed again and return to the small intestine where they grow into adult worms.

Adults and older children may have no symptoms. When signs and symptoms do occur in children, they may include:

  • Worms that resemble earthworms in a bowel movement

  • Worms coming out of the nose or mouth

  • Stomach pain

  • Coughing

  • Loss of appetite

  • Fever

  • Wheezing

  • Weight loss or failure to grow

If worms cause a blockage of the intestine, a child may develop severe pain and vomiting, with a tender, bloated, and hard belly.

Diagnosis and treatment

If your child has a history and symptoms that suggest roundworms, your child's doctor will order a stool sample so that a small amount of the child's feces can be studied under a microscope to look for roundworm eggs or worms.

In most cases, roundworms can be easily treated by taking a medication that kills the worms in about three days. Medications called albendazole and pyrantel are commonly used in the U.S. In rare cases, surgery may be needed to relieve a severe intestinal obstruction caused by roundworms.

Be sure to contact your child's doctor if you suspect roundworms.
