What Is Ascariasis?
Ascariasis (as-keh-RYE-eh-sis) is an intestinal infection caused by a worm called
Ascaris lumbricoides.
Treatment with prescription anti-parasite drugs usually clears up the infection
within a week.
What Causes Ascariasis?
Ascaris eggs are found in soil and human feces (poop). They get into the
body when someone eats or drinks something contaminated with the eggs.
Most people with ascariasis got it by:
- putting dirty hands in their mouth
- eating fruits or vegetables that weren't peeled, washed, or cooked
Globally, ascariasis is the most common human worm infection. Infections are more
common in warmer or tropical climates, especially in areas with poor sanitation or
crowded living conditions. They're rare in the U.S. due to strict sanitation practices.
Children are more likely to get ascariasis. They tend to put things in their mouths,
including dirt, and often have poorer hygiene habits than adults.
What Happens in Ascariasis?
Swallowed eggs pass into the intestines,
where they hatch into larvae. The larvae go through the intestinal wall and enter
the bloodstream. Then, they travel to different organs, such as the liver, lungs,
brain, or kidneys. Larvae in the lungs can climb up the airways to the throat, where
they are swallowed. The swallowed larvae return to the small intestine and grow and
mature into adults. This happens about 2 months after the egg was swallowed.
Adult worms live in the small intestine for 1 to 2 years. They can be as thick
as a pencil and can measure from 5 to 14 inches long. A person can have many worms
at the same time if many eggs hatch. And each female worm can produce over 200,000
eggs per day. When they come out in the poop, they start the life cycle all over again.
What Are the Signs & Symptoms of Ascariasis?
Most people with ascariasis don't have any symptoms. Those who do can have symptoms
that range from mild to severe depending on how many worms are in the intestines.
Symptoms also depend on which part of the body is affected. They include:
- coughing up worms
- wheezing or trouble breathing
- worms in stool (poop)
- loss of appetite
- fever
- nausea and vomiting
- diarrhea
- belly pain or bloating
Kids are more likely than adults to complain of gastrointestinal symptoms. That's
because their intestines are smaller and more likely to get blocked by the worms.
A large mass of worms in the intestines can lead to malnutrition and poor growth.
It can also block the appendix and other organs, leading to appendicitis
or problems with the liver, pancreas, or gallbladder.
Is Ascariasis Contagious?
Ascariasis doesn't spread from one person to another. To become infected, a person
has to swallow the worm's eggs.
How Is Ascariasis Diagnosed?
Doctors can diagnose ascariasis by looking at a worm that comes out when someone
coughs or poops. They can also test stool
samples for eggs.
Sometimes, imaging tests (like an X-ray, ultrasound, or CT scan) can show the worms
in the belly or chest.
How Is Ascariasis Treated?
Doctors treat ascariasis with prescription anti-parasite drugs. Symptoms usually
stop within 1 week of starting treatment.
Very rarely, doctors do surgery to remove the worms. This usually happens only
if they block the intestines or cause problems with the liver, pancreas, or gallbladder.
Can Ascariasis Be Prevented?
Good sanitation is the best way to prevent ascariasis.
Children adopted from developing nations may be tested for worms even if they have
no symptoms. Kids who live in areas where ascariasis is common might be treated for
it even if they haven't been diagnosed with an infection.
It's also important to:
- Teach kids to wash their
hands well and often, especially after using the bathroom and before eating.
- Keep kids from putting things in their mouths, especially if they're around soil
that may be contaminated with poop.
- Wash, peel, or cook all fruits
and vegetables before eating them.
When Should I Call the Doctor?
Call your doctor right away if your child has any symptoms of ascariasis. This
is especially important if you adopted your child from a developing country or you
traveled to areas where ascariasis is common.
Also call the doctor if your child's symptoms don't get better with treatment or
if new symptoms start.
Date reviewed: November 2019