Tennessee medical experts answer questions about parasite-induced ‘explosive’ diarrhea illness
We brought your concerns to two doctors for answers.
What This Story Is About
- Nashville has fewer than 10 confirmed cases of cyclosporiasis as the CDC looks into the parasite-induced illness that’s impacted more than half of states.
Why It Matters
- People usually get the illness after consuming contaminated water or contaminated produce.
What Happens Next
- The CDC is still working to officially determine the cause of the outbreak, but Michigan health officials believe they may have narrowed it down to contaminated lettuce.
Catch Up
NASHVILLE, Tenn. (WSMV) - Cyclosporiasis has made it to Tennessee, so we asked you what you’d like to know about the illness.
Here are the answers we got from Dr. Dontal Johnson, an associate professor of pediatrics at Meharry Medical College and Dr. William Schaffner, professor of infectious disease at Vanderbilt University Medical School.
I think I may have had this before. Is this a new illness?
“No, it’s been around. For a long, long, long time, Cyclospora has been around. It’s a parasite. It kind of ebbs between, I think it’s like May, June, July, all the way to August is where we normally see a rise in it. It’s usually, again, contaminated produce, contaminated drinking water,” Dr. Johnson said. “Usually the cases are pretty low, maybe in the hundreds or something for the whole entire year. Now we are getting up into the thousands of confirmed cases with maybe 5,000 or more cases out there that they’re waiting to kind of continue the testing for.”
“It’s not a new illness. We have cases of cyclospora that occur each year, in the late spring and into the early summer, scattered across the country, so this infection has been around, but in small scattered numbers, the occasional tiny little outbreak here or there. But what we’re having now, just in its size, the number of cases, and its geographic distribution, that’s unprecedented,’ Dr. Schaffner said.
Do we know what’s causing the spike in cyclosporiasis cases this year?
“I don’t believe so. Sometimes there’s an outbreak, right? There’s a contaminated big manufacturer and they, you know, send out a lot of products,” Dr. Johnson said.
“A lot of people buy those products and the spread just happens, right? So what they do is they kind of backtrack and see, can they locate where it was that most of these outbreaks have come from? If it was a company, if it was a produce section, if it was a certain, you know, brand or something like that. And so that’s what we’re trying to do now is figure that out.”
Dr. Schaffner added, “I wish we did. You know, the disease detectives at the CDC and their counterparts in state health departments, our own included, they are working very hard to try to find out what the source of it is. Because we anticipate that there’s a single common source out there that has spread whatever it is, produce probably, across a wide part of the country.”
Does cyclosporiasis really last a whole month?
“It can. So that’s what it’s claim to fame is, is that it can last months. And it’s not that it’s lasting the entire month, is that you get hit, you get better,” Dr. Johnson said. “That’s kind of how we identify it in the story or the history of the present illness. When they come in, they tell me, ‘Hey, I’ve been having this watery diarrhea, these explosive bowel movements, but I got better, and then it hit me again.’”
“This is a persistent illness. You can have your acute illness, get over it, and it can then reoccur, get over it, and reoccur again. And yes, it can stretch itself out for weeks, even beyond a month. So all the more important reason to get it well diagnosed, because we can treat it with an antibiotic and stop it,” Dr. Schaffner said.
If you think you’ve contracted cyclosporiasis, what precautions should you take at home to protect your family?
“Hand washing, hand washing, hand washing. Making sure, you know, if you got it, then maybe go through and do a deep dive inventory on any produce that you may still have left. And if you know for sure you had it, then maybe we just go buy some more to some different produce in there just to be safe. But the main thing is get tested,” Dr. Johnson said.
“This parasite doesn’t affect other animals, so we don’t have to worry about our pets. Interestingly enough, at least to date, there’s no human-to-human transmission. We have to get it from contaminated food, so that can put some concerns to rest,” Dr. Schaffner said.
Should we avoid produce altogether right now?
“No, produce is good. We want you to eat fresh produce, always, always, always. We just want you now, during these situations as well as in general, just always make sure you’re doing the right thing for yourself and your family when it comes to washing your produce off. You don’t got to buy any special disinfectant sprays,” Dr. Johnson said.
He continued, “There are certain parameters where when you cook in some of your vegetables and things like that, you can kill this parasite with a high enough heat volume, as well as, again, just stripping it off those outer layers of lettuce leaves and then some of the other produce, fresh fruits and things like that.”
" In general, I think it is good advice, first of all, to wash everything that comes into the house, your produce and your fruit. The adage is wash it, peel it, or cook it. Now, how thorough do you want to be? That depends a little bit on your risk tolerance," Dr. Schaffner said.
“I know that there are people out there who are avoiding salads at the present time and going into restaurants and not eating those fresh salads. They want to put that off. I know that there are people who are getting head lettuce at home and peeling off the outside layers, discarding those because they think they’re more likely to be contaminated. So on an individual basis, you’ll have to decide just how careful you want to be.”
How should we wash our produce? Should we use any special disinfectants or products?
“Clean, running water, even if it’s pre-washed stuff. Again, that’s the best guidance that we have currently. I know baking soda and the fizz looks really, really great and good, but again, clean, running water, strip out some of the outer portions, that’s all you gotta do,” Dr. Johnson said.
“I would say wash your produce thoroughly. Different people will have different ways of doing it. I will tell you that one of my professors used to say, ‘The only way you can sterilize lettuce is with a blowtorch.’ So take that under advisement,” Dr. Schaffner said.
Does the temperature of the water matter when washing produce or washing your hands?
“That’s more to do with like cooking. And again, just making sure that you’re, it’s not ice cold water, but it’s not boiling hot water that you’re washing your hands with, somewhere in the middle. It’s more of the practice of getting in the habit of washing your hands, getting in the habit of washing your produce,” Dr. Johnsons said.
“I think the amount of water, the thoroughness of the washing, is more important than the temperature because you’re literally trying to wash off this parasite from the surface of the produce. The water is not trying to kill the parasite. It’s trying to rinse it down the drain,” Dr. Schaffner said.
Should we avoid foods like salad when going out to eat? Should we take any further precautions at restaurants?
“I would not say that yet. Again, we’ve had 24 cases in Tennessee and we’re backtracking to see where those are, but salads are healthy for you. Fresh produce is healthy for you. And the benefits, I would say, definitely outweigh the risk of you avoiding greens,” Dr. Johnson said.
He continued, “Hand washing, just good hand washing. The good thing about it, our city and our state restaurants and things like that, they are also in the mix in terms of being checked. So if there’s an outbreak and we’re backtracking it to some place that’s local, then they’re aware of it, they’ll let the patrons know that have dined there and things like that. We still want people to go out. We still want them to have a good time. Just good, good hand washing and things like that.”
“That’s the risk question. How careful do you wish to be? A lot of people are avoiding uncooked food in restaurants at the present time. It’s perfectly reasonable,” Dr. Schaffner said.
Can the cyclospora spread through pools and splash pads?
“No, we’re not worried about transmission there. That person to person transmission isn’t really a big way that this is transmitted, is more kind of from produce and things like that and contaminated water sources kind of more related to what they clean the produce with and stuff like that,” Dr. Johnson said.
“Well, cyclosporiasis can be transmitted by contaminated water, but at the present time, there’s no evidence that water is involved in this outbreak,” Dr. Schaffner said.
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