What is an ascaris infection?
An ascarid is a worm
that lives in the small intestine. Infection with ascarids is called
ascariasis (ass-kuh-rye-uh-sis). Adult female worms can grow over 12
inches in length, adult males are smaller.
How common is
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
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
You or your children
can become infected after touching your mouth with your hands contaminated
with eggs from soil or other contaminated surfaces.
What should I do if I think I
See your health care
How is diagnosis of ascaris
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
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.
I am pregnant and have just
been diagnosed with ascariasis. Can I be treated?
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
- Avoid contacting
soil that may be contaminated with human feces.
- Do not defecate
- Dispose of diapers
- 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 eating.
Should I be concerned about
spreading infection to the rest of my household?
No. Infection is not
spread from person to person.
For more information:
Sarinas PS, Chitkara
Ascariasis and hookworm. Semin Respir Infect 1997 Jun;12(2):130-7
This fact sheet is for
information only and is not meant to be used for self-diagnosis or as a
substitute for consultation with a health care provider. If you have any
questions about the disease described above or think that you may have a
parasitic infection, consult a health care provider.