Cyclospora
- Cyclospora [SIGH-clo-SPOR-uh] infection
is a newly emerging parasitic illness that
can cause severe diarrhea.
- People most likely get cyclospora infection
by eating food or drinking water that was
contaminated with stool from an infected person.
- Cyclospora infection is treatable with antibiotics.
- Cyclospora infection can probably be prevented
by avoiding food or water that might be contaminated
with stool.
What is cyclospora infection?
Cyclospora infection is a rare infection of
the intestines that can cause severe diarrhea.
What is the infectious agent that causes
cyclospora infection?
Cyclospora infection is caused by Cyclospora
cayetanensis, a microscopic one-celled parasite.
How do people get cyclospora infection?
Cyclospora is different from many other organisms
because it is not infectious when it is passed
in the stool of an infected person. Cyclospora
needs days or weeks after being passed in a
bowel movement to become infectious. Therefore,
it is unlikely that the parasite is passed directly
from one person to another. People most likely
get Cyclospora infection by ingesting food or
water that was contaminated with stool from
an infected person. It is unknown if animals
can be infected and pass infection to people.
In 1996, a large outbreak of cyclospora infection
in the United States and Canada was caused by
imported raspberries. It is not clear how the
fruit became contaminated, but it might have
happened when fruit touched the ground or when
contaminated water was sprayed over fruit fields
by sprinkling systems.
What are the signs and symptoms of cyclospora
infection?
Cyclospora infects the small intestine and
usually causes watery diarrhea, with frequent,
sometimes explosive, bowel movements. Other
symptoms can include loss of appetite, loss
of weight, bloating, increased gas, stomach
cramps, nausea, vomiting, muscle aches, low-grade
fever, and tiredness. Some people who are infected
with cyclospora have no symptoms.
How soon after exposure do symptoms appear?
The time between becoming infected and developing
symptoms is unusually long for a disease spread
by food -- about 1 week. If not treated, the
illness can last for a few days to a month or
longer. If untreated, it can also return one
or more times.
How is cyclospora infection diagnosed?
Identification of this parasite in stool requires
special laboratory tests that are not routinely
done. A health-care provider must specifically
request testing for Cyclospora. Because Cyclospora
can be difficult to diagnose, more than one
stool sample might be needed.
Who is at risk for infection?
Anyone can get Cyclospora infection.
What complications can result from cyclospora
infection?
Without treatment, the infection can cause
weeks of severe tiredness, loss of appetite,
dehydration (loss of fluids), and weight loss.
What is the treatment for cyclospora infection?
Cyclospora infection is treated with an oral
medicine that is a combination of two sulfa-based
antibiotics: trimethoprim and sulfamethoxazole.
For people with diarrhea Cyclospora can be difficult
to diagnose. If Cyclospora infection is suspected,
people should consult with their health-care
provider before taking medicine for diarrhea.
How common is cyclospora infection?
Cyclospora infection is very rare in this country,
and most states do not keep track of the number
of cases. In the past, the infection was usually
found in persons living or traveling in tropical
countries. Increasingly, however, cases are
being recognized in the United States and Canada.
In the United States, infection is most common
during spring and summer.
Is cyclospora an emerging infection?
Yes. The first human cases were reported in
1979, but cases began being reported more often
in the mid-1980s. This may be partly because
of the availability of better tests to detect
the parasite in stool specimens. Several recent,
very large outbreaks linked to raspberries,
mesclun lettuce, and possibly basil have increased
concerns about Cyclospora and stimulated health
officials to learn more about how it is transmitted
and what factors contribute to its spread.
How can cyclospora infection be prevented?
Based on what is known about Cyclospora, the
best way to prevent infection is to avoid eating
raw or undercooked foods or drinking untreated
water that could be contaminated with stool.
Cooking can kill Cyclospora, and freezing might,
too. As a general food safety measure, always
wash fresh produce, even if it is to be peeled
before eating.
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 questions about the disease
described above, consult a health-care provider.