As officials seek the cause of the cyclospora outbreak in several states linked to food and vegetables that can cause diarrheal illnesses, there's another parasite you might encounter in summer outings that can cause similar symptoms.
KERA 's Sam Baker talks with Dr. Neima Briggs, assistant professor in infectious diseases at the School of Public Health at UT Southwestern Medical School, about cryptosporidium – also known as "crypto."
Dr. Briggs: Outbreaks that we see in the United States are associated with common recreational water sites like splash pads and water sports areas, lakes — anywhere where there's potential for contamination from human or from livestock.
Baker: Even though it's not part of the cyclospora outbreak, are we seeing more cases than usual?
Dr. Briggs: I'm not aware of a change in the numbers. We do have a relatively large number of cases in the U.S. annually, somewhere around 800,000 cases per CDC.
That's an estimate because the cases that actually get reported are really the tip of the iceberg, which are about 2 to 5% of those confirmed cases for cryptosporidium.
Baker: Why such a small amount though that gets identified?
Dr. Briggs: For a lot of people, having kind of mild-to-moderate diarrheal symptoms may not be enough to drive them to go to their provider, so even when they do show up to their provider, they may take a wait-and-see approach because if it's a more common bacterial toxin mediated diarrhea or viral diarrhea, there's not specific treatments for that. So, a wait-and-see approach is reasonable in those individuals.
Baker: How then do you prevent crypto?
Dr. Briggs: The best is prevention. Even a very, very small amount of this parasite getting into the water can infect another person, which was part of what makes it so transmissible.
It's also highly chlorine resistant. So, even in parks or recreation sites that do the appropriate prevention, it can spread. If your child or yourself have any sort of diarrheal symptoms, it's best to avoid, of course, these water parks and for crypto, really not going to a site where you can potentially spread to other people for two weeks is really important.
I would say if you have immune-compromising conditions or a loved one of yours does, during the hot summer months where it's more common to be transmitted, it's another reason to kind of take caution to where you're going in terms of large public water parks where spread can be more common.
Baker: So, I won't say stay home, but, stay away.
Dr. Briggs: Yes, it's hard, but if you can, of course, avoid drinking the water. And the other thing is that, after large rainstorm events, if you're going to go out on the lake or into a creek bed and do some swimming, that runoff, especially from livestock, can infect the waterways. And so it's good for both bacteria as well as for crypto to avoid swimming in it for the days after a large rainstorm.
Baker: How do you treat it?
Dr. Briggs: There is a medication that we can use called nitrozoxanide. It's kind of a broad anti-parasitic sort of treatment, and it's not a perfect treatment. And thus, we need to make sure that they not only tolerate the treatment but that their symptoms resolve afterwards.
Baker: Is there anything you do or can do after that or just wait until it passes?
Dr. Briggs: Usually it's that and a lot of supportive care. So, I often advise my patients that they need to make sure that they're staying well hydrated, having access to fluids and electrolyte replacement is going to be really important. Products such as Pedialyte that are electrolyte-balanced that are kind of ideal for those situations are important to have.
A good rule of thumb is you should be having to go urinate at least every four hours or so during these diarrheal illnesses. That will be a good sign that you are replenishing your fluid sufficiently to kind of combat what you're losing through the diarrheal illness.
RESOURCES:
What you need to know about the cyclosporiasis outbreak
Protect Yourself and Your Family During the Ongoing Cyclospora Outbreak
It's not just produce. Where else can 'explosive diarrhea' bug hide?
About Cryptosporidium or cryptosporidiosis ("crypto")
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