To protect yourself from cyclosporiasis—a parasite-borne illness causing explosive, watery diarrhea—you should prioritize cooking produce when possible, scrubbing firm fruits and vegetables with running water, and considering buying whole heads of lettuce instead of bagged salads. Because the parasite is often linked to produce sourced from other parts of the world, sourcing food locally and utilizing freezing for berries can further reduce the risk of infection.
Cyclosporiasis is currently tearing through the U.S., with nearly 2,000 infections reported this year. In Michigan alone, the numbers are staggering: 1,562 cases and 44 hospitalizations, a massive spike compared to the state's typical average of about 50 cases per year.
This isn’t just a localized fluke. More than 20 states have reported cases, including Ohio, where 177 people have fallen ill. The parasite, cyclospora, doesn’t care about borders, and it certainly doesn’t care about your diet plan. It hitches a ride on fresh produce, waiting for a way into your system. While it’s rarely fatal, the experience is a grueling marathon of cramping, bloating, and nausea that can persist for a full month if left untreated.
The Invisible Hitchhiker in Your Salad Bowl
The real terror of cyclosporiasis is its stealth. Unlike a typical stomach bug, this parasite has a wide “incubation window,” meaning symptoms can emerge anywhere from two days to two weeks after you’ve eaten the tainted food. By the time you’re sprinting for the bathroom, the salad you ate ten days ago is long gone, making it nearly impossible for you—or health officials—to remember exactly what caused the flare-up.
This isn’t our first dance with this pathogen. In 2013, the U.S. saw more than 600 cases, and in 2018, more than 500 people were sickened across the country by contaminated McDonald’s salad meals. The common thread? Fresh produce. Bagged salads, basil, cilantro, peas, and berries have all been the primary suspects in previous outbreaks. The current crisis is particularly vexing because, as of July 10, the Michigan Department of Health and Human Services has yet to identify a specific grower or supplier as the source.
The struggle to trace these outbreaks is compounded by the FDA’s difficulty in proving contamination at the farm level. In 2020, an outbreak seemed linked to Florida-grown produce shipped to Illinois, but the agency couldn’t conclusively prove the farms were the origin. The parasite is elusive, and we don’t even know the exact “infectious dose” required to make a person sick, which makes preemptive testing a challenge.
Why Globalized Dining Makes Us Vulnerable
We’ve built a food system based on the luxury of convenience—raspberries all year round. But that convenience comes with a biological tax. Because cyclospora is more prevalent in tropical and subtropical regions, our reliance on a centralized, global distribution network creates a highway for the parasite to travel from a distant field to a suburban grocery store.
Joseph Eisenberg, a professor of epidemiology and global public health at the University of Michigan, notes that this centralization is exactly how these outbreaks scale. When a single contamination event occurs in one part of the world, that produce is shipped throughout the area and it could go anywhere in the world.
Adding to the chaos is a depleted surveillance infrastructure. Dr. Kathleen Linder, the hospital epidemiologist at the Veterans Affairs hospital in Ann Arbor, points out that the CDC has rolled back some of its national reporting programs. This shift has pushed the burden of tracking onto state health departments, leading to a “lag” in information that makes it harder to see the full picture of an outbreak in real-time.
A Tactical Guide to Cleaning Your Produce
Since we can’t currently point to a specific “bad” brand of spinach or berries, the responsibility falls on the consumer. The goal isn’t just to rinse the dirt off; it’s to physically remove or kill a resilient parasite.
Heat is your best weapon. Cooking produce is the most effective way to eliminate cyclosporiasis. For those sticking to raw foods, a rigorous cleaning protocol is non-negotiable. Wash everything under running water. For firm items like cucumbers or melons, use a produce brush. If you see a bruise or a damaged spot on your lettuce, don’t just eat around it—cut the damaged area away entirely.
Be especially wary of the “pre-washed” label. Dr. Linder advises re-washing these items regardless of the packaging claims. If you’re buying lettuce, consider buying whole heads. Peel away the outer layers, separate the inner leaves, and wash them individually. For green onions, remove the bulby root and the outer skin before a thorough rinse.
Berries are the trickiest of all due to their bumpy surface. To stay safe, consider using frozen raspberries—freezing is believed to reduce or eliminate the parasite—or cook them into a jam or compote. Additionally, keep a strict eye on your leftovers; any unused food should be refrigerated within two hours to prevent further bacterial or parasitic growth.
When to Seek Medical Intervention
While most people recover from cyclosporiasis with rest and hydration, the risk is higher for those who are immunocompromised. The primary danger isn’t the parasite itself, but the dehydration caused by “explosive” bowel movements.
According to medical guidance from experts like Dr. Linder, you need to seek immediate medical attention if you experience:
- Severe dizziness.
- An inability to keep fluids down.
- Very dark urine.
If you suspect you’ve been infected, contact your healthcare provider and your local health department immediately. Your data point might be the one that finally helps officials trace the source of this outbreak.
Ultimately, this outbreak is a symptom of a fragile food chain. Until we find a way to better surveil our imports, a little extra effort at the kitchen sink is the only real shield we have. Are you changing your shopping habits this summer, or does the convenience of bagged salads still outweigh the risk?
