An ascarid is a worm that lives in the small intestine.
Infection with ascarids is called
(ass-kuh-rye-uh-sis). Adult female worms can grow over 12 inches in
length, adult males are smaller.
How common is ascariasis?
Ascariasis is the most common human worm infection. Infection
occurs worldwide and is most common in tropical and subtropical
areas where sanitation and hygiene are poor. Children are infected
more often than adults. In the United States, infection is rare,
but most common in rural areas of the southeast.
What are the signs and symptoms of an ascaris infection?
Most people have no symptoms. If you are heavily infected, you
may have abdominal pain. Sometimes, while the immature worms
migrate through the lungs, you may cough and have difficulty
breathing. If you have a very heavy worm infection, your intestines
may become blocked.
How is an ascaris infection spread?
Ascarid eggs are found in the soil. Infection occurs when a
person accidently ingests (swallows) infective ascarid eggs. Once
in the stomach, larvae (immature worms) hatch from the eggs. The
larvae are carried through the lungs then to the throat where they
are then swallowed. Once swallowed, they reach the intestines and
develop into adult worms. Adult female worms lay eggs that are then
passed in feces. This cycle will take between 2-3 months. Pigs can
be infected with ascarids. Occasionally, a pig ascarid infection
can be spread to humans. This occurs when infective eggs, found in
the soil and manure, are ingested. Infection is more likely if pig
feces is used as fertilizer in the garden. Crops then become
contaminated with ascarid eggs.
How can I get ascariasis?
You or your children can become infected after touching your
mouth with your hands contaminated with eggs from soil or other
How is a diagnosis of ascaris made?
Your health care provider will ask you to provide stool samples
for testing. Some people notice infection when a worm is passed in
stool or is coughed up. If this happens, bring in the worm specimen
to your health care provider for diagnosis. There is no blood test
used to diagnose an ascarid infection.
What is the treatment for ascariasis?
In the United States, ascaris infections are generally treated
for 1-3 days with medication prescribed by your health care
provider. The drugs are effective and appear to have few
side-effects. Your health care provider will likely request
additional stool exams 1 to 2 weeks after therapy. If the infection
is still present, treatment will be repeated.
Can I be treated if I am pregnant?
Infection with ascarid worms is generally light and is not
considered an emergency. Unless your infection is heavy, and your
health may be at risk, treatment is generally postponed until after
delivery of the baby.
How can I prevent infection with ascarids?
Avoid contacting soil that may be contaminated with human
Do not defecate outdoors.
Dispose of diapers properly.
Wash hands with soap and water before handling food.
When traveling to countries where sanitation and hygiene are
poor, avoid water or food that may be contaminated.
Wash, peel or cook all raw vegetables and fruits before
Should I be concerned about spreading infection to the rest of
No. Infection is not spread from person to person.
Centers for Disease Control and
Prevention, August 1999
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a