What is cryptosporidiosis?
Cryptosporidiosis is an infection that causes diarrhea. It is sometimes called Crypto.
It is caused by a parasite found in stool. You can get this infection after eating
food or drinking water that is contaminated with stool. This includes swallowing water
while swimming or drinking from infected streams and other water sources. You can
also get infected if you touch things or surfaces contaminated with stool. You can
also get the infection from another person.
The parasite has an outer shell. Because of this shell, using chlorine to clean water
may not kill the parasite. Cryptosporidiosis is one of the most common causes of waterborne
disease in the U.S.
What causes cryptosporidiosis?
Cryptosporidiosis is caused by the parasite Cryptosporidium. Once inside your body,
the parasite passes through your digestive tract and infects your intestines and stool.
Anything contaminated with the infected stool can pass the infection on to other people.
Who is at risk for cryptosporidiosis?
The parasite is found throughout the world. But you are more likely to get the infection
if you travel to rural areas in developing countries. Or you can get it if you often
eat or drink in areas where sanitation is poor. Outbreaks have also occurred in the
U.S. when water supplies or swimming pools become infected.
The disease is spread by accidentally swallowing anything that has come into contact
with the stool of a person or animal with the infection. This includes:
Swallowing water contaminated with the parasite. The parasite can be found in swimming
pools, hot tubs, lakes, rivers, springs, ponds, or streams contaminated with sewage
Eating uncooked foods tainted with the parasite.
Swallowing the parasite picked up from surfaces contaminated with the stool of an
infected person. This includes bathroom fixtures, changing tables, and diaper pails.
Cryptosporidiosis is normally not a serious disease in healthy people. But it can
lead to a life-threatening illness for people with a weak immune system. Those at
What are the symptoms of cryptosporidiosis?
Each person may have slightly different symptoms. These are the most common symptoms:
Loose or watery stools
You may not have any symptoms. If symptoms do develop, they often last about 2 weeks
and sometimes longer. But even if you have no symptoms, the parasite is passed in
your stool for up to 2 months. During this time, you are at risk of spreading the
infection to others.
How is cryptosporidiosis diagnosed?
Your healthcare provider will look at a stool sample. Sometimes multiple stool samples
(usually 3) will be needed since this parasite is found only intermittently in the
stool. You will need special testing because tests for this disease are not routinely
done in labs.
How is cryptosporidiosis treated?
Most people with a healthy immune system do not need to be treated. Cryptosporidiosis will
resolve on its own. In those who have weak immune systems, the focus of treatment
is often on getting the immunity back. Otherwise, a medicine called nitazoxanide can
be used to treat this parasite. Sometimes an antidiarrheal medicine such as loperamide
may be given for symptom relief.
Your healthcare provider will figure out the best treatment for you based on:
How old you are
Your overall health and past health
How sick you are
How well you can handle specific medicines, procedures, or therapies
How long the condition is expected to last
Your opinion or preference
No treatment works fully against the infection. If you have a healthy immune system,
you will likely recover on your own. People who are in poor health or have a weak
immune system may get a more serious infection. In some cases, you may need to take
medicine for diarrhea. It’s important to drink plenty of fluids to stay hydrated.
What can I do to prevent cryptosporidiosis?
There is no vaccine to prevent cryptosporidiosis. The best way to protect yourself
is with good personal hygiene. Also:
Wash your hands thoroughly with soap and water after using the toilet or changing
Wash your hands thoroughly before eating or making food.
Wash and peel all raw fruits and vegetables before eating.
Don't drink water from lakes, rivers, springs, ponds, or streams, unless they have
been filtered or chemically treated.
Don't drink any water or eat any food that may be tainted.
When traveling to countries where the water supply may be unsafe, do not drink unboiled
tap water. Also do not eat any raw foods washed with tap water. Choose steaming hot
drinks, such as coffee and tea, and pasteurized fruit drinks. Make sure bottled water
is safe to drink.
Many home and camping/hiking water filters can remove Cryptosporidium. Read the label
When should I call my healthcare provider?
Call your healthcare provider right away if your symptoms return or get worse, or
you have new ones.
Key points about cryptosporidiosis
Cryptosporidiosis is an infection that causes diarrhea. It is caused by a parasite.
Most people get the parasite after swallowing food or water tainted with stool. This
includes swallowing water while swimming.
Diarrhea, vomiting, and weight loss are the most common symptoms.
Dehydration is the main complication.
Good personal hygiene can help prevent it. You should also stay away from unclean
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells
At the visit, write down the name of a new diagnosis and any new medicines, treatments,
or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed and how it will help you. Also
know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that
Know how you can contact your provider if you have questions.