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A weekly show from the folks at East Lansing Info breaking down all the news and happenings in East Lansing, Michigan.
Hello, everyone, and welcome to this week's episode of East Lansing Insider. I'm East Lansing Info's deputy editor, Anna Liz Nichols. And this week, we're talking about the cyclosporiasis outbreak. And, yes, that's still going on. For a lot of listeners, you might have started hearing about cyclosporiasis for the first time around June.
Anna Liz Nichols:Maybe joked about how you couldn't have a salad anymore, but ultimately, more than fourteen thousand cyclosporiasis cases have been found in Michigan during this outbreak, and two individuals have died in the state as part of this outbreak. To give scale and how this has impacted Michigan, the time we're recording this podcast on Thursday ahead of Sunday, again, Michigan makes up more than fourteen thousand of the about seventeen thousand cases identified by the CDC in The US. Cyclosporiasis isn't a new problem. The CDC even identifies a season for it from the start of May to the end of August, and, typically, it only impacts around two thousand people in The US, but sometimes even less. I'm joined this week by Joan Rose, a public health water microbiologist and director of Michigan State University's Water Alliance.
Anna Liz Nichols:Now, Joan, thank you for joining me today. I think despite us now all getting a bit inundated with information about this parasite's Cyclospora and the intestinal illness it causes, cyclosporiasis. The public doesn't really generally know what this is and why this is all happening. We just kind of watch out for what leaf or berry we're not supposed to eat or what food chain we're not supposed to go to this week. But I was wondering if you could explain what Cyclospora is and how it gets in our food system.
Joan Rose:Hello, Anna. Thank you for having me on. Yeah. You know, this is it's it's quite a phenomenon and it's a mouthful, Cyclospora. And it's an interesting little protozoan, we call it a parasite, and it's in the animal kingdom.
Joan Rose:And I think what's really unique about this organism is that it needs a host to replicate and the only host that it's found is in humans. So Cyclospora replicates in the intestinal tract in the gut, in our gut. It goes through a life cycle and it produces these egg like structures in our feces, basically in our poop. And they're called oocysts. And this is how we get sick.
Joan Rose:When it replicates in our gut, it produces this severe diarrhea and we can get very dehydrated. So this little protozoan parasite Cyclospora replicates in our gut and that's how we get sick. Not everybody gets sick. A percentage of us will get severe diarrhea and we get very dehydrated. And of course two people died from the illness, that's unusual but with people that have underlying health conditions, they're at higher risk of these severe consequences.
Joan Rose:And so it can be very serious for some of our special populations in our community.
Anna Liz Nichols:So how does this enter our food systems? Because how we're being told to avoid the illness is to avoid certain, fruits and vegetables. Also, different restaurants that use those fruits or vegetables. How does this illness get to us through the food system?
Joan Rose:Yeah. Like I said, Cyclospora replicates only in humans. And when it first appeared in, the '90s in The United States, there were many studies that looked and looked to see if it replicated in animals and if animal waste could also be a cause of the contamination. But it's really just human waste. So that means that human fecal waste or sewage, because most of our fecal waste winds up in water, winds up in The United States, of course, in sewage treatment plants and goes into facilities.
Joan Rose:And so that's how it gets in into the environment. So there's a number of ways that it gets into the food chain. It can get into the food chain by workers. If somebody's infected and they're not using good hygiene or don't have gloves or washing facilities, and they're already infected and excreting the osis, they can transfer the osis onto the food in the field or that kind of thing. And then of course, secondarily, wastewater contaminated water with feces, that's how we get massive contamination is when wastewater and fecally contaminated water is used either to irrigate, to wash our produce, to process it, put it in our little bags, these kinds of things.
Joan Rose:We use water for these things and if that water gets contaminated, then the oocysts go along with the water. And so we know it comes from humans, we know it comes from human fecal contamination. And this large of an outbreak, this is just massive. It's hard to really calculate that a few infected workers could contaminate that much produce that is distributed. So in my view, I believe that it was due to water that was contaminated.
Joan Rose:And somewhere along the food chain, that contamination got into the system and onto our crops. Now, is it that we're worried about fresh produce? You know? You might I don't know if you were gonna ask that, Anna, but, you know, you got lettuce. We got, you know, basil.
Joan Rose:We've got raspberries. These are the things that, have been linked to Cyclospora.
Anna Liz Nichols:And a lot that are famously hard to wash. Like, when they said blackberries at one point, raspberries, same vein. I'm like, how do you you do your best to wash those items, but that's a lot of cravons.
Joan Rose:No. Those little hairs on the strawberries and raspberries and the little crevices. You know these things are microscopic. This is a parasite so it's very, very small. We only see it under the microscope so it can get in there.
Joan Rose:And, it's very hard to wash them off. So there's a number of reasons why produce is associated. One, when Cyclospora is first excreted from someone that's infected, it has to mature. It cannot cause an illness in the next person immediately. It's like a little baby kind of having to mature in the environment before it can cause the next illness.
Joan Rose:So the oasis undergoes maturation, what we call maturation. So that takes time. So you could imagine where we have problems in daycare centers and restaurants, where we've got fecal contamination on our food and somebody else gets sick, that happens immediately, but not with Cyclospora. It has to be in the environment seven to ten days at a special temperature for it to mature. So of course, lettuce, raspberries, all these things, they have that kind of condition, right?
Joan Rose:So if it gets on this food, it has time to mature and become infectious. The other reason of course is that we don't usually cook these types of foods and we eat them raw. And they are, as you mentioned, very difficult to wash the Cyclospora off. And so this is kind of like all these factors make this the perfect little protozoan parasite to contaminate our, produce and fruit in that way and cause disease.
Anna Liz Nichols:There's a lot of information being disseminated about Cyclospora and and the illness. Me tumbling over my words, not even attempting to say that. But you'd mentioned earlier that there there is a belief that it might have been a few infected workers. I was wondering, is it is it generally believed that this started because of infected workers and that that led to it or the water being used or the water nearby agricultural systems being infected, which ultimately would become infected by us, by human beings, by with that.
Joan Rose:Yeah. I mean, you know, I I wouldn't say that we have evidence that it's infected workers. We know that it was someone that was infected. Mhmm. And, you know, anytime we go into a community, you know, and we see that's another reason.
Joan Rose:When we go into a single home, let's say I go to a septic tank and I sample there, you know, somebody has to be infected for me to find the pathogen in that household. There might be four people in that household, six people in that household, so somebody has to be infected. But when you go to a community sewage, we can find hundreds of different pathogens because in community sewage, it seems like there's always somebody infected in the community. With Cyclospora, we don't know very much because the monitoring data is very scarce. But we do know that people can be infected without knowing that they're ill, they don't get treated.
Joan Rose:So they excrete the OOC for a long time. And that means in any community sewage, we might be able to find it here and there as we sample. The studies globally that have been done early on with this protozoan did show that you could find the protozoan in untreated sewage anywhere from one percent up to forty percent of the time. So they were looking at different countries and different times of the year. They didn't know who was infected.
Joan Rose:So, you know, anytime we go to community sewage, we know we're gonna find these pathogens, and we suspect that we could find Cyclospora at some percentage of the time, because someone in the community is infected. Yeah.
Anna Liz Nichols:You know, in your recent article that I read that got me interested in talking to you for this, you mentioned in in some states, though, you know, sewage water gets treated, it's not always treated in such a way that gets rid of those oocysts. And if you could remind us what those oocysts are and why that allows, you know, this to flourish.
Joan Rose:Yeah. So, you know, I'm I've been working in the field what we call wastewater reuse or reuse. And, you know, water is, you know, on our Blue Planet is so important. We already know that. But we also use water for everything.
Joan Rose:We use water to for, you know, chip manufacturing and because it's so good at dissolving and carrying things. We also use it to carry our wastes away from our communities, from our homes. So we use a water based sewage system. Now we have the technology to recover that water by treating it. And that means that if we put enough treatment processes in there or membranes and other things, we can get very highly purified water.
Joan Rose:But for most wastewater treatment systems, we only have routine secondary treatment. And then we'll have disinfection in many cases before they release the wastewater to our environment. That's under just a discharge permit. So secondary treatment is not designed to remove these microbes very easily. Remember, the O cyst is very small, it's microscopic.
Joan Rose:It's bigger than a bacterium, but way smaller than an algae. It could be similar to, you know, the real small algae that you can only see under the microscope. And so we wouldn't even see Cyclospora with our eye. We would have to look under the microscope and magnify, you know, this, a lot of times. So it's very, very small.
Joan Rose:And the other thing about the oocyst, it's like an egg like structure. And it's very resistant to the disinfection we use. So in wastewater, we use disinfection to kill a lot of our microbes. We can manage the disinfection, we can use chlorine chlorine and adjust the concentration and adjust it. But chlorine does not kill Cyclospora osis.
Joan Rose:And so the wastewater system would have to have maybe UV disinfection, advanced UV disinfection, maybe some ozone, some more advanced treatment. So we know most wastewater systems do not have these advanced treatments. In the wastewater reuse arena, they use this advanced treatment. And especially in states where they do a lot of wastewater reuse. And you can imagine if you're in California right now or Arizona, and you've heard about the Colorado River and the lakes drying up that serve water to the communities in the West.
Joan Rose:They really need water. So they are using reuse to be sustainable. And they know they have to monitor for these special pathogens, protozoa like Cryptosporidium, which is related to Cyclospora. We've got a couple of protozoa there that are hard to say. And we've got giardia, another one, and then we've got the viruses, we've got the bacteria.
Joan Rose:So we've got all these hundreds of microbes in wastewater that we monitor for, we understand if we use advanced treatment, we can kill them, we can remove them. And if we're just getting started with reuse in many states, there may be limited information and expertise to set up the advanced treatment so that they're removing these types of pathogens. But in particular, because we use disinfection, what we call disinfection to kill these microbes in our water treatment processes, and we mostly use chlorine, it is just resistant to that process. And so that's one of the concerns.
Anna Liz Nichols:You mentioned, you know, some states by virtue of their their own biome, like ones that experience drought like California, they more would have to more heavily rely options. Does Michigan lean heavily into that, or are we particularly blessed by virtue of the Great Lakes?
Joan Rose:Yeah. So, you know, the other you know, I guess the other side of the coin here is that, agriculture uses a lot of groundwater, We know that. That's a major ingredient. Really. And, and so, groundwater is somewhat protected from these bigger oocysts like Cyclospora.
Joan Rose:So that's one advantage to using groundwater is it it it's not completely protected from microbes. Mhmm. But, there is more protection depending on how well the the the wells are made and the the aquifer and all of that kind of thing. In Michigan, we still use quite a bit of groundwater for irrigation. If we use surface water, they do have to monitor it for E.
Joan Rose:Coli, which is a bacterium that's found in feces. But one of our problems is that the bacteria don't always represent the protozoal like Cyclospora. As you can imagine, they're very different organisms. Bacteria are small, they do different things than these little animals. So our indicator system is not adequate for some of these other pathogens we worry about.
Joan Rose:So that's why we try to come up with more information and more technology that can help us take care of those risks. The other thing in Michigan and in the Great Lakes in general, we are blessed with water. We know that. We've got beautiful water. We can be stressed during the summer because of our infrastructure.
Joan Rose:We pump too much and it's hot and it hasn't rained. And we wanna protect our water source. And so there's things like data centers coming in and other industries that wanna use water, And reuse is an option for us to say, yes, we're gonna continue to protect our water and we're gonna continue to be sustainable in how we manage water. And then we're gonna think about the circular economy. And water is part of that circular economy.
Joan Rose:Any time we reuse water, waste water, any time we have reuse, we wanna be sure that it is microbiologically safe. And even if it's for industry and and, you know, in occupational settings or whatever. So we have to be sure that we're taking care of these microbes. And reuse is not very prominent, particularly in Michigan. I think that it's less than, point 1% of the total volume of wastewater.
Joan Rose:Most wastewater gets treated normally by routine activated sludge and is discharged to our rivers. But where we do see some reuse is some package plants like at rest stops and things like that. There's a few places where they're trying to reuse the water, here and there, but it's a very small percentage now. But in the future, I I think that reuse will be part of our one water approach to managing both quantity and quality. Mhmm.
Joan Rose:And that means that we're going to do more advanced treatment on even our routine wastewater systems because we're gonna protect our rivers and our lakes and our beaches. So I think that's gonna be our future. And the more we can plan for, you know, controlling these microbes, the better as we, invest, you know, in that water rich circular water economy of the future.
Anna Liz Nichols:Yeah. And to borrow from your piece that you wrote again, I saw that you said the first time you studied Cyclospora was in the field out in Florida, in 1995. I think it was about, forty five cases that you had that had happened at the time. How has our understanding of detection and, you know, resolution of of these these these outbreaks changed in the last thirty or so years. Mind you, we're having a much larger outbreak now and one that I don't maybe you would know better than I am.
Anna Liz Nichols:Maybe the largest we've seen with Cyclospora.
Joan Rose:I do think this is the largest outbreak documented, to date. And it's surprising. We have learned a lot about this pathogen. We've learned a lot about Cyclospora and its biology and its genetics and its life cycle. I think on the water side and the food safety side, maybe we haven't invested as much because we saw it as rare.
Joan Rose:We saw this as all, forty five cases, it never showed up before. And then I think several years in a row, we had outbreaks of Cyclospora in The United States due to raspberries in Guatemala. They had banned raspberries from coming in. And it was really a shame they'd already just done some kind of agreement to try to advance the global food market. And I remember that year we had banned it in The United States, but Canada had not banned those raspberries.
Joan Rose:And they went into Canada that next year, and, they got some cases. And so that was pretty good evidence that it was coming from these fields, and they still were struggling to say, where is the fecal contamination source coming from, and how do we stop it? And even now in this big outbreak with all our tools, we're still struggling like, is it more than one produce? Is it more than one farm? Was it imported from the global food market?
Joan Rose:It's really incredible. So in this field, in the water microbiology field, we have now started to take advantage of all the advancements in microbial detection. And these are advanced molecular tools and techniques. We call it PCR for short. This is polymerase chain reaction.
Joan Rose:We don't wanna say that, so we say PCR. Now most people have heard of PCR because that is the test we use for SARS, COVID two.
Anna Liz Nichols:Oh,
Joan Rose:okay. And what is PCR? So it is a, I call it a biological copy machine. What we do is we can copy the gene code, the genetic code of specific organism. So we design a little system and we have an instrument.
Joan Rose:We take the water sample, we recover the DNA like CSI on TV. So we take that DNA out of the water and out of the microbes that are in that water and we design this little copy machine to look for copies. We make copies and look for these copies of a specific organism. So now we can design a PCR test for any organism, almost any organism we want in water. Because we do know the genetic code, we do know how to design these things.
Joan Rose:Now there's been some glitches along the way. FDA has an approved method for PCR. I think the clinical labs, if you get sick and you give a fecal sample, they'll test it with PCR to see if you have Cyclospora. So this has advanced our ability to take a water sample, and test for Cyclospora. And so, we've had to learn some things like how do we concentrate the oocysts out of water and sewage?
Joan Rose:How do we get rid of the interferences? How do we break open the oocysts and get the DNA? These are method issues that we've been evaluating. But I think we're at a stage where any pathogen that shows up in water, we can use these advanced molecular tools. You know what was another interesting thing, another development in science that I think would benefit us if we use these tools more often in water and food safety, are source tracking tools.
Joan Rose:Now these are our targets that allow us to say, is the fecal contamination come from humans, or does it come from birds? Or does it come from cows? Where's it coming from? And that's why we call them source tracking. So these source tracking tools, we have at least two markers that are very good to track human fecal contamination.
Joan Rose:And they're pretty easy tests. They've been used to study sewage and sewage contaminated waters around the world. We have publications where global labs, we all collaborated and we evaluated these markers. These markers could be used to better evaluate when human fecal contamination is getting into our food chain, is getting into our water systems, is getting into our irrigation systems. And if we could track that better, we could come up with strategies for preventing first the fecal contamination, and, secondly, maybe treating water or treating things differently before, you know, we contaminate our our food chain.
Anna Liz Nichols:Is there any other component of this that might be helpful for maybe even specifically Michigan residents, East Lansing residents to understand about what's going on right now?
Joan Rose:Well, for quite a long time, some consumer groups have advocated to be sure that we know where our food is coming from. You'll there's the farmers markets are out right now. And and one thing about Cyclospora, because it needs that temperature to mature, you kind of see it in the summer, you know, in the late spring, summer, and fall.
Anna Liz Nichols:There's a season for it, according
Joan Rose:to beauty. For it shows up. And, you know, so can you go to the local farmer's market? That's the same time the farmer's markets are expanding. Eat local.
Joan Rose:I one of my friends said, oh, I'm so glad I have my garden. You know? Because she loves lettuce. And so I think those are things. Of course, we can try to wash, but it's not always possible to be assured that you've washed your vegetables and fruits well enough to be protective.
Joan Rose:I do think that we could freeze berries for sure, not maybe lettuce. But because this is a little animal, it doesn't do really well with freeze thaw. So if you had some washed it really well, froze it, there would be some extra protection there, but we can never be sure. And we have no way to test. And so I think consumers can say to grocery stores and others, we do want to know where our food comes.
Joan Rose:We recognize that we have a global food chain, and we have full grocery stores because of that, which is a benefit to us and to our nutrition. But we can also ask to try to understand where our food is coming from. I think that we're going to have to do more as professionals, water microbiologists and food safety professionals. We're going to have to do more to look at breaking the contamination chain. But, yeah, individuals I think can maybe go local during that season, and that helps your local economy, your farmer's market, that kind of thing, fresh food.
Joan Rose:And we're living in a world right now where we find out about these events, And once they start expanding, we find out about them very quickly. And I do think that it's everything from consumers wanting more safety. And we don't want our drinking water, our beaches, our food to cause any deaths. We don't want them to cause outbreaks. We want our food and water to be safe.
Joan Rose:And then that means that it's professionals, it's the government agencies that investigate these outbreaks. That whole array of individuals are going to be important to be assured that we have safe water and safe food in the future.