Unseen Guests: Listeria, E. coli, and the Summer Parasite on Our Produce

That perfect strawberry can't tell you if it's safe 🍓

This week on Old Ways, New Days, we sit with the unseen guests that ride home on our produce — Listeria, E. coli, and the summer parasite making its rounds across the US right now: Cyclospora.

In this episode:

🔬 Why "clean" and "safe" are not the same thing

🚪 The five doorways of contamination

🦠 Meet the guests — and why Listeria loves your fridge

🌀 Cyclospora: the parasite you can't wash off, why it takes a week to start and weeks to finish, and the good news that it's treatable.

Old rituals, made new — kitchen and homestead prevention that actually works

Because the answer isn't fear. It's attention.

Resources: 

https://www.cdc.gov/outbreaks/index.html

https://www.cdc.gov/ecoli/about/index.html

https://search.cdc.gov/search/?query=listeria&dpage=1

https://search.cdc.gov/search/?query=cyclospora&dpage=1

https://www.fda.gov/safety/recalls-market-withdrawals-safety-alerts

https://www.usatoday.com/story/shopping/trending/2026/07/14/tips-to-safely-grow-produce-at-home/90917497007/

Transcript

SPEAKER_01 0:00

You're excited that the grocery store had a sale on berries, so you picked up a couple cartons of strawberries. You get home, you take your strawberries out of the bag, and you rinse them under cool water. You turn them in your hands, watching the water run clear. You pick out the soft one, set it aside. The rest look perfect. Firm, red, sweet, ready. And they probably are. But here's the quiet truth we're going to sit with today. Everything you can see about that berry tells you almost nothing about whether it's safe. The bruise you can see, the mold you can smell, the soft spot you can feel. But the things that actually make people sick, the bacteria, the parasite, leave no mark, no smell, no taste, no warning. Our senses were trained by our ancestors to catch rot. They were never trained to catch this. Today we're talking about the unseen guests that sometimes travel home with our fresh produce, Listeria, E. coli, and the parasite that shows up every summer like clockwork, Cyclospora. We're going to talk about where they come from, whether you can identify them, how to keep them out of your kitchen and off your homestead. And we're going to do it the way we always do. Honest about the science, reverent about the food, because the answer here isn't fear, the answer is attention. Welcome, witches, pagans, heathens, spiritualists, and anyone interested in living sustainably.

SPEAKER_00 1:35

This is Old Ways, New Days, where the old ways meet the good dirt. I'm Kayla, and I'm Noel. And each week we explore the sacred art of living close to the land. From compost to covens, chickens to charms, we're reclaiming self-sufficiency, seasonal living, and ancestral wisdom.

SPEAKER_01 1:56

Whether you're stirring your cauldron or your soup pot, this is a space for wild-hearted folk walking the homesteading path with intention, magic, and muddy boots. We're talking today about you know all of the things that make you sick when you buy produce in the grocery store. Especially with some new random bug or parasite that's going around right now, causing uh people to have diarrhea, and it's on everything, it seems like. It's raspberries and lettuce and tomatoes. So we're gonna talk about, we're gonna break that down today and we're gonna talk about. So let's begin with the hardest idea, because everything else rests on it. Clean and safe are not the same thing. We were raised to trust our senses. Grandmother taught us to smell the milk, to feel the g give in a peach, to look at the meat and no. And for most of human history, that wisdom kept people alive. Spoilage is a sensory event, souring, softening, the bloom of molds, and the turn of a smell. But the organisms we're talking about today are not spoilage, they are contamination. And contamination is silent. A leaf of lettuce carrying E. coli looks exactly like a leaf that isn't. A cantaloupe carrying Listeria smells exactly like one that's safe. A raspberry carrying cyclospora tastes exactly as sweet. There is no bruise for bacteria, there is no odor for a parasite. The food can be beautiful, freshly picked, glistening, perfect, and still be carrying something that will make you sick days or even weeks later. This is not meant to frighten you, it's meant to reorient you. Because once you accept that you cannot rely on your eyes and nose alone, you stop looking for the impossible, the bad-looking berry, and you start doing the things that actually protect you. Which is exactly where we're headed. To understand these guests, we follow them back to the doorway they came through. A produce contamination almost always comes through one of a few doors. The first door is water. Water is the great connector of the growing world. It's used to irrigate the fields, to wash the harvest, to cool the crop, to rinse the equipment. And water carries whatever is upstream of it. If irrigation water is drawn from a source touched by animal waste, by sewage, by runoff after a heavy rain, the water can carry pathogens directly onto the growing plant, onto the leaf, into the tiny crevices of a berry. This is why leafy greens and low-growing berries come up again and again in outbreaks. They grow close to the ground, close to the splash, and they have textured surfaces that hold on to what lands on them. The second door is manure and soil. Raw, uncomposted animal manure is rich with life. And some of that life is very is the very bacteria we're trying to avoid. E. coli lives in the guts of cattle and other ruminants, entirely at home there, harmless to the animal. But applied to a field as raw manure or carried by runoff from a nearby pasture, it moves on to the food. This is why proper composting matters so much. And we'll come back to that on the homestead side. Composting done right with real heat held over time is one of the oldest and best defenses we have. The third door is animals and their traffic. Wildlife wandering through a field, birds overhead, rodents in a storage barn, a neighbor's livestock with a fence that isn't quite doing its job. Each of these can carry contamination onto crops that were, until that moment, perfectly clean. The fourth door is hands and surfaces. Ours, the harvesters, the packers, the unwashed hands, the shared knife, the cutting board that touched raw meat and then touched the salad. This is the door closest to home, and it's the one we have the most power over. And then there's the fifth door worth naming on its own, the cold. Most bacteria slow down in the refrigerator. Listeria does not. Listeria is the guest that keeps working in the cold. It can grow slowly at refrigerator temperatures. So a contaminated food sitting in your fridge doesn't necessarily stay at the same low level. Over days, listeria can quietly multiply. That single trait is why it deserves its own respect, and we'll meet it properly in a moment. Notice something about all five doors. Water, soil, animals, hands, cold. Hilda! Sorry, the cat knocked my brand new mouse on the floor. And I hope she didn't break it. Because it's a brand new mouse. Alright, let's start that over again, Hilda. Alright, notice something about all five doors. Water, soil, animals, hands, cold storage. These aren't exotic. They're the ordinary elements of growing and keeping food. The same L elements our ancestors negotiated with every single season. What's changed isn't the door. What's changed is the scale. One contaminated field today can be washed in one shared bath, bagged and shipped to a thousand kitchens in a week. The doorway is old. The reach is new. Hilda. Nope, come on. Can we get off the table, sweetie pie? Okay. Sorry for that interruption, listeners. It's the joy of cats, right? So let's introduce the two bacterial guests by name, because knowing their habits tells us how to guard against them. Most E. coli is harmless. It lives in all of us right now, doing quiet work. But certain strains produce a toxin, and those are the ones behind the outbreaks. It's the home its home is the gut of cattle and other animals. Its usual path to us is through fecal contamination, contaminated water, raw manure, or unwashed hands somewhere along the line, landing on leafy greens, sprouts, and other fresh produce. What it does, stomach cramps that come on hard, and diarrhea that is often bloody, it usually arrives within two to eight days of eating the contaminated food. Most healthy adults weather it and recover, but in young children and older adults, E. coli can trigger a severe complication that damages the kidneys. A genuine medical emergency. This is why we take it seriously, especially for the little ones. Listeria is the patient one, the cold loving one. As we said, it can grow in the refrigerator, which makes it a special concern for foods that are kept cold and eaten without cooking. Pre-cut fruits, ready-to-eat salads, deli items, sprouts, certain soft produce. Two things make listeria distinct. The first is timing. Listeria can have a very long incubation. Symptoms may not appear for days, and in some cases, weeks, after the contaminated food was eaten. That long, quiet delay is part of what makes it so hard to trace back to a source. The second is who it targets. For most healthy people, listeria can cause mild illness or not at all. But for pregnant people, newborns, older adults, and those with weakened immune systems, it is generously dangerous. It can cause severe illness, and in pregnancy it can threaten the baby. This is why the guidance for pregnant people around certain pre-cut and ready-to-eat foods is so cautious. It's not fussiness. It is a real and specific risk. So hold these two in your mind. E. coli, fast gut-born, hardest on the very young and very old, and listeria, slow, cold hard cold tolerant, and hardest on the pregnant, the newborn, the elderly, and the immune-compromised. And now the guest you actually asked about, the one making its rounds across the country right now and every summer on fresh produce, the parasite. Haha, do a little germinal. Its name is Cyclospora. The illness it causes is called cyclosporasis, and unlike Listeria and E. coli, it is not a bacterium at all. It is a single-celled parasite. That difference matters because it changes almost everything we know about how it behaves and how we fight it. Cyclospora is a creature of warm weather. In the United States, cases climb through the late spring and summer, think roughly May into August, every year, like a season of its own. Outbreaks and clusters of Cyclosporasis appear, and they are consistently tied to fresh produce. Over the years it has been linked to items like fresh herbs, such as cilantro and basil, and to fresh leafy greens, bagged salads, and various fresh vegetables and berries. It's a warm season fresh produce parasite, and its arrival is one of the most predictable things in the food safety calendar. So you're probably wondering how it spreads. And this is the strange, important part. Cyclospora spreads through the fungal oral root, meaning the parasite is shed in stool and through contaminated water or produce, ends up swallowed by the next person, but here is the crucial detail. When cyclospora is freshly shed, it is not immediately infectious. It needs time. Days to weeks in the right warm, moist environmental conditions outside a host to mature into its infectious form. Think about what that means. It means person-to-person spread is essentially not how this works. You cannot catch it catch it by shaking a sick person's hand the way you might pass a cold. The parasite has to sit out in the environment and ripen first, which points the finger squarely at contaminated water and the produce that water touched, somewhere upstream, days before that salad ever reached your plate. Here is the hard news, and I want to be very clear about it because it's the part people most need to hear. You cannot reliably wash Cyclospora off your produce. The chlorine and sanitizer washes that reduce many bacteria are not considered effective against this parasite. And rinsing at home, as good and worthwhile a habit as it is, does not reliably remove it either. Cyclospora is tenacious in a way ordinary rinsing doesn't overcome. And unlike some threats, you can't cook your salad. And the very appeal of fresh cilantro, fresh ras fresh berries of any kind, actually, crisp greens is that we eat them raw. There's no heat step to fall back on. So prevention for cyclospora happens upstream at the level of clean water and safe growing practices, long before the food reaches you, which is exactly why traceback sourcing and staying informed about active advisories matters so much for this particular guest. So what does it do to the body? Cyclosporasis is above all a parasite of prolonged watery diarrhea. That's its signature, and it's relentless in a way that surprises people. Symptoms usually begin about a week after exposure, often around seven days, and they can last for weeks if untreated. This is not a 24-hour bug. People describe watery diarrhea that comes and goes that seems to lift and then returns, a relapsing, remitting pattern that can drag on for weeks. Alongside it, a loss of appetite, weight loss, stomach cramps and bloating, increased gas, nausea, and deep fatigue. Some people run a low fever. That exhausting, waxing and waning course is one of its most telling features. Now, the good news, and there is real good news here, cyclosporasis is treatable. Unlike a virus, you simply have to outlast. This parasite responds to specific antibiotic treatment prescribed by a doctor. So if you've eaten fresh produce and then found yourself with watery diarrhea that won't quit, that lingers on for days, then lifts, and comes back, that is a reason to see a healthcare provider and to mention the produce and the pattern specifically. Because standard stool tests don't always look for cyclospora unless it's requested. Naming it can be the difference between weeks of misery and the right prescription. That's the whole shape of this guest, a warm season parasite riding in on fresh produce through contaminated water, invisible to your senses, unbothered by your rinse, patient enough to take a week to start and weeks to finish, and thankfully answerable to the right treatment once it's named. So the question we all want answered, standing at the sink, berry in hand, can I tell? For every guest we've named today, the honest answer is no. Not at home. Not with your eyes, your nose, or your tongue. There is no color that means listeria, no smell that means E. coli, no taste that means cyclospora. The contaminated leaf and the clean leaf are identical. That's the whole cruel elegance of it. So let's put down the impossible task of spotting the bad one and pick up the things that are worth noticing. You can still notice spoilage, and you should still discard the slimy, the moldy, the sour, the off. That's real, and your senses are good at it. Just understand that you're removing rot, not removing risk. You can notice damage, deep bruising, splits, cuts in the skin. These are entry points and hiding places where contamination can shelter, where bacteria can multiply. A damaged surface is worth cutting away or setting aside. And the one modern tool that actually does let us see the unseen is the recall notice, the public health advisory where the CDC and the FDA trace an outbreak back to a source. They issue an alert. That alert is the modern equivalent of the old village crier, the voice that runs through the community calling out news you could not have learned on your own. Our ancestors had watchmen and criers in the shared memory of the village. We have public health agencies. So the single most powerful identification habit you can build is simple. When you're going to eat something raw and there's an active season for a parasite like Cyclospora, take 30 seconds to check whether there is a current advisory. I'm deliberately not naming a specific brand or grower today because active recalls change week to week. And by the time you hear this, the list will have turned over. The living current list lives with the CDC and the FDA. Let them be your crier. Check the source, not last month's headline. Here's where it turns hopeful. Because while we can't see these guests, you have real power over them. And most of that power lives in small, repeatable rituals, the kind our grandmothers would recognize instantly. Let's do the kitchen first. Wash your hands. Before you handle produce and after. Twenty seconds, warm water, soap. This is the oldest and most effective ritual we have, and it never stopped being true. Rinse your produce under running water, even the things you'll peel, because your knife drags the outside in. Rinsing won't defeat cyclospore, as we said, and it won't guarantee safety, but it reduces bacterial load and washes away soil, and it's still worth doing every single time. Skip the soap and the bleach on your food. Plain running water is the guidance. Scrub the firm ones. Melons especially. Cantaloupe with its netted rind is a classic Listeria concern. Scrub the whole outside with a clean brush before you ever cut in, so the knife doesn't carry the rind's contamination into that sweet flesh. Keep things separate. Raw meat and its juices away from produce, separate boards, separate zones, wash in between. The salad greens and the raw chicken should never share a surface. Respect the cold and respect the clock. Refrigerate, cut, and ready-to-eat produce promptly. Remember Listerious Cold Trick. The fridge slows most things, but not everything, so cold storage buys you time, not immortality. Eat pre-cut and baked items within a reasonable window rather than letting them linger. And when you cook, cooking wins. Heat is the great equalizer. It ends bacteria and parasites alike. For the vulnerable especially, a cooked vegetable carries far less risk than a raw one. Now the homestead, because many of you grow your own, and prevention here happens in the soil and the water. Compost properly. This is the big one. Raw manure is a doorway. Finished, hot, composted manure is a wall. Composting that reaches and holds real heat over time breaks down the pathogens that live in raw waste. Give it the heat and give it the time. Don't rush young compost onto food crops. A year, maybe two, is always a good time measure. Mind your water source. Know where your irrigation water comes from. Be especially thoughtful after heavy rain, when runoff can carry contamination from pastures and roadways onto ponds and low grounds. And if you do a water catchment system off your roof, remember. You have squirrels and birds that probably poop on your roof, and that poop is now in your water. So if you're using that water to water your vegetable garden, maybe use it to water flowers instead. Fence out the traffic. Keep livestock and as much of as you can wildlife out of the growing beds. A fence that actually works is a food safety tool. Harvest clean. Clean hands, clean tools, clean baskets. Don't harvest in the same bin that carried something questionable. And handle gently. Every split and bruise you prevent is one less hiding place. And care especially for the vulnerable. If you're cooking for someone pregnant, for a newborn, for an elder, for someone whose immune system is fighting another battle, lean toward cooked over raw, toward freshly prepared over long stored, toward extra caution around the pre-cut and the ready to eat. This isn't fear. It's the oldest instinct we have, the community protecting its most tender members. Looking at that list again, wash your hands, rinse the food, keep the clean from the unclean, compost with patience. Know your water, protect the vulnerable. This is nothing new in any there's nothing new in any of it. These are the food rituals of every careful kitchen and every wise homestead across every culture that ever survived a summer. We just understand why they work now. The science gave us the reason, the answers the ancestors already gave us the rhythm. I want to close where we started. At the sink, with the berry in your hand. Because it would be easy to walk away from an episode like this a little afraid of your own kitchen, afraid of the salad, afraid of the fruit bowl. And that is not what any of this is for. Fresh food is one of the greatest gifts of being alive. The strawberry in June, the first tomato still warm from the vine, the bright snap of cilantro. We are not here to talk you out of the harvest. We are here to help you meet it awake. The unseen guest has always been part of the human table. Our ancestors didn't know its name. They didn't have the word cyclospora or listeria or a microscope to see E. coli. But they had the rituals. Wash the hands, rinse the roots, keep the manure aged and the water clean, cook for the sick and the small. They built these habits out of hard-won memory, generation on generation, without ever seeing the thing they were guarding against. We are luckier. We can see it now. We know its habits, we know its seasons, its doorways. And when we take that knowledge and pour it back into those same old rituals, the washing, the tending, the patient composting, the listening for the crier's call, we are doing something quietly beautiful. We are joining the long line of people who fed the families with both love and attention. Not with fear, not but with care. Eat awake, friends, rinse your greens, scrub your melons, mind your water, and when the summer parasite is making its rounds, let the CDC and the FDA be your village crier. Watch the world closely, the way growers and cooks always have, because that's how the old ways become new days. Until next time.