July 15, 2026
Cyclospora Outbreak July 2026
Last updated: July 14, 2026/4:00 PM — This page will be updated as new information becomes available.
Public health officials in Michigan, Ohio, West Virginia, and Kentucky are currently investigating a multistate outbreak of cyclosporiasis, and there has been a lot of conversation online and in the news. IFPA has been in contact with state and federal health officials since early July, and we've put together answers to the questions we're hearing most based on what is known right now.
We may update this page as new information is released about this current outbreak.
Frequently Asked Questions:
What is Cyclospora and what does it do?
What is Cyclospora? Cyclospora cayetanensis is a microscopic parasite that can cause an intestinal illness called cyclosporiasis. It's been a known, if uncommon, cause of foodborne illness in the U.S. for decades, with cases typically rising in the warmer months (May – August). Of note, infections with Cyclospora generally have a favorable outcome, even in immunocompromised patients, and no significant long-term health consequences have been reported.
The good news: most people who get sick recover fully, even those with weakened immune systems, and there haven't been any lasting health effects reported.
What are the symptoms? The most common symptom is watery diarrhea, often along with loss of appetite, weight loss, cramping, bloating, nausea, and fatigue. Symptoms can start, on average, about a week after exposure and, without treatment, can last from a few days to a few months. It's treatable with prescription antibiotics, but can also self-resolve.
What should I do if I think I'm sick? Contact your healthcare provider, especially if you have prolonged watery diarrhea. Cyclosporiasis is treatable with prescription antibiotics, and a healthcare provider can confirm diagnosis with a stool test.
Are some people at greater risk than others? Yes. Most healthy adults recover fully with appropriate antibiotic treatment. The illness can be more severe and longer-lasting for people with weakened immune systems, including those living with HIV, organ transplant recipients, or people on immunosuppressive medications. If you or someone in your household is immunocompromised and experiencing symptoms consistent with Cyclospora, it's worth contacting a healthcare provider promptly and specifically asking about Cyclospora testing.
Current Outbreak
Has a specific food been identified as the source of this outbreak? No specific food, farm, grower, or supplier has been confirmed as the source of this outbreak. CDC, FDA, and state health departments have not identified or confirmed any product as the cause. It is important for consumers to understand that as of writing of this update, no fruit or vegetable, including lettuce, tomato, or cilantro, has been confirmed as a source through laboratory or environmental testing.
We understand that, based on patient questionnaire responses, Michigan officials have linked a number of cases to Mexican-style quick-service restaurant chain(s) and have mentioned lettuce as one product currently under scrutiny as part of that inquiry. Tomato and cilantro have also come up as possible vehicles being discussed. It is critical to understand what this does and does not mean: these are leads being investigated, not a confirmed source. This signal does not appear to explain all reported cases, and to our knowledge, no product or environmental sample has tested positive or confirmed contamination in connection with any of these leads. Any claim naming a specific food or company as the confirmed source of this outbreak right now is getting ahead of the data, and consumers should not avoid any particular fruit or vegetable based on speculation. CDC's own outbreak page for this investigation is titled 'Cyclosporiasis Outbreak with Unknown Source,' and states directly that a specific food item has not yet been confirmed as the source.
While investigators are focusing on foods, IFPA continues to raise concerns about recent municipal sewage overflows in the greater Detroit/Toledo region and the likelihood of these events impacting the quality of drinking water (especially water wells) and recreational water in Lake Erie and surrounding bodies of water. Water exposure remains an important line of inquiry alongside food.
While foods are traditionally listed as sources of Cyclospora infections when sources of past outbreaks were established, the majority of infections have no known cause. Complicating our understanding of Cyclospora's persistence in the environment: detection methods used in the past had significant reliability limitations, which is part of why FDA developed and now recommends a more precise protocol for detecting Cyclospora in environmental and food samples. That current method, however, is not yet governed by an international testing standard, and not all labs use it consistently, which is addressed further in the Testing section below.
Has any product been recalled in connection with this outbreak? No FDA or state-issued recall has been announced in connection with this outbreak as of this writing. We are aware of media reports describing precautionary menu changes at some restaurant locations, including signage referencing a recall; we cannot confirm the basis for that specific language, and it does not correspond to any recall listed by FDA. If a specific product is identified and a recall is issued, FDA and CDC will announce it publicly, and we will update this page immediately.
Why are some restaurants removing certain menu items? Some restaurants, including a limited number of locations of a quick-service chain, have reportedly removed specific produce items as a “precaution” while the investigation continues. This kind of precautionary action does not mean a source has been confirmed. We'd encourage anyone with questions about a specific restaurant's decision to reach out to that company/location directly.
Are these case numbers unusual? Yes. Michigan has reported 3,762 cases, and Ohio (at a county-by-county level) has reported over 1,100 cases as of mid-July, both far above their typical annual totals. Separately, CDC has identified a specific cluster of more than 400 cases across Michigan, Ohio, West Virginia, and Kentucky that it considers linked, meaning CDC believes these particular cases may share a common source; this is a subset under focused investigation, not the full case count for those states. Illness onset in this linked cluster began on June 22 and include case onsets up to July 9.
It's worth understanding that public health agencies routinely monitor cyclosporiasis cases in groups, or clusters, across the country each season as a normal part of surveillance, and this year is no different in that respect. CDC has noted it is looking at a few such clusters right now, in addition to the main Michigan-Ohio-West Virginia-Kentucky cluster described above. This is a standard part of how outbreaks are investigated, comparing cases across different areas to see whether any share a common thread, not a sign that the situation is broader or more severe than what's already been described here.
Nationally, CDC reports 1,645 confirmed domestically acquired cases since May 1, across 34 states, with more than 5,100 additional cases still under review. CDC states this is substantially higher than the 249 cases reported nationally by the same point last year.
Why does Cyclospora tend to show up in certain places or times of year? Cyclospora is closely tied to environmental conditions. The parasite needs warmth and moisture to become infectious, so cases tend to rise in the summer, and clusters can follow periods of heavy rainfall or water system disruptions, which can affect water used in irrigation or food handling as well as recreational water areas (however, this correlation does not hold in locations outside of continental North America). There was documented, significant rainfall and combined sewer overflow activity in parts of the affected region in mid-June. IFPA believes this timing warrants consideration as a possible contributing factor, alongside food, though we are not aware of confirmation that state or federal investigators are currently examining it.
How it spreads
How does someone get Cyclospora? People get infected by ingesting contaminated food and water. Importantly, a person who is sick with cyclosporiasis cannot pass it directly to someone else the way a cold or flu spreads; the parasite needs to spend time (typically days to weeks) in the environment, usually in soil or water, before it becomes capable of infecting someone else. That's part of why finding the exact source of an outbreak takes time.
How does Cyclospora end up in a production environment? Because Cyclospora cayetanensis only infects humans, it can only enter a farm environment if human waste is not properly managed, for example wastewater reaching agricultural water or soil in a way that shouldn't happen. Oocysts shed by an infected person are not immediately infective though. They need 7-15 days in a warm, moist environment to mature before they can cause illness, which means the contamination pathway almost always runs through the environment rather than directly from person to produce.
What does water have to do with Cyclospora on a farm? While infected individuals are the only source of Cyclospora, water is believed to be a way that Cyclospora travels into and through a production environment. Surface water sources including rivers, canals, ponds, and reservoirs can carry oocysts if exposed to sewage or inadequate sanitation upstream. If irrigation or processing water comes into contact with a compromised sewage line, a poorly maintained septic system, or runoff from a nearby facility with inadequate sanitation controls, it can carry the parasite to crops before or after harvest. Soil can also harbor oocysts for weeks to months, and flooding or runoff can move them into production areas.
How does Cyclospora actually get onto fresh produce? Once the parasite is present in water or soil, there are a few main ways it can end up on a crop.
Overhead watering is the most direct route for leafy greens and herbs, since water sprayed onto the plant lands right on the leaves people eventually eat. Drip irrigation, which waters the roots instead of the leaves, carries meaningfully lower risk for this reason, though it doesn't remove every source of contamination, since splashing soil can still reach low-growing plants. Heavy rain or flooding can do the same thing, splashing contaminated soil or water directly onto crops.
Contamination can also happen after harvest, not just in the field. Water used for washing, cooling, or packing produce, or contact with dirty surfaces or equipment at a packing facility, can introduce contamination even after the crop leaves the ground. This is part of why both farm water and post-harvest processing water are separately regulated, which we cover further below.
Can farms, municipal water systems, or recreational water facilities like pools add chlorine to water to eliminate Cyclospora? No, and this is an important distinction from most other waterborne pathogens. Chlorine and other standard antimicrobial chemical treatments are not considered effective against Cyclospora, regardless of whether they are applied at the farm level in an irrigation system, at a municipal water treatment facility, or in a recreational water setting such as a swimming pool or splash pad. This includes the chlorination levels typically used in all of those settings.
Alternative treatment approaches such as UV light, ozone, or microfiltration can reduce the parasite in water and may be appropriate depending on the source and the level of risk identified.
This is one of the reasons prevention at the source matters so much for Cyclospora specifically. For farms, that means the annual water assessment and source protection are the primary line of defense rather than chemical treatment after the fact. For municipalities, standard disinfection protocols that reliably handle bacteria and viruses do not provide the same assurance for this parasite. For pools and other recreational water facilities, the chlorine levels maintained for routine sanitation are not sufficient to kill Cyclospora, which is why people who swallow water in a pool or other recreational water body are not protected the way they might be from other waterborne illnesses. People traveling to regions where Cyclospora is more common should also be aware that locally treated tap water and recreational water may not eliminate the risk, even when it meets local treatment standards. CDC's July 14 health alert reinforces this directly, stating that 'no EPA-registered disinfectant products have been demonstrated to be effective against Cyclospora.
What consumers can do
What can I do to reduce my risk? Standard food-safety practices apply: wash your hands before and after preparing food, rinse fresh produce under running water, and keep preparation surfaces clean. These are good practices at any time, not just during an active investigation. During recreational activities (swimming, water sports, visiting aquatic parks), it is imperative to follow advice of public health officials based on water quality.
Can chlorine or washing remove Cyclospora from produce? Not completely, and this is important to understand about this specific parasite.
Chlorine and other common disinfectants don't work well against it. Health officials have found that Cyclospora may resist routine chemical disinfection, including chlorine, and no approved disinfectant has been shown to fully get rid of it. This is different from many other germs, where chlorine-based cleaning does the job.
Washing helps, but doesn't remove it completely either. Rinsing produce under running water reduces contamination, but isn't likely to remove all of it. This parasite tends to stick to produce more than many others do.
Cooking and peeling work best. Heating food to 158°F or higher kills Cyclospora, so cooking is the most reliable way to get rid of it when possible. Peeling also works well for fruits and vegetables with skin you can remove, since the parasite sits on the outer surface.
Bottom line: washing is still worth doing, and pairing it with cooking or peeling when you can gives the best protection. But washing alone shouldn't be treated as a guarantee that produce is completely free of Cyclospora.
Should I stop eating fruits and vegetables? No. Health officials are not telling people to stop eating fruits and vegetables. They remain an important and healthy part of your diet.
In Michigan, lettuce and salad greens have come up often when investigators ask sick people what they ate before getting ill. Because of this, officials there are recommending some extra precautions for now: buying whole heads of lettuce instead of pre-washed bags, removing the outer leaves, washing it thoroughly, and cooking it when possible.
It's important to know that this guidance is specific to the affected areas right now, not a recommendation for the rest of the country. There's no indication that lettuce or produce sold elsewhere in the U.S. is affected.
Officials have also been clear that none of this is confirmed. Lettuce might turn out to be the cause, or the real source might end up being something else entirely. No specific product, grower, or supplier has been identified. These precautions are simply a smart way to stay safe while the investigation continues in the affected region, not a sign that lettuce or any other produce should be avoided.
Testing and Traceback
How does a doctor test for Cyclospora if someone is sick?
Testing for Cyclospora requires a stool sample, but it will not show up on the standard parasite test that most labs run as a matter of routine. A doctor must specifically ask the lab to look for it, and the lab must use the right technique to find it. This is one of the reasons Cyclospora infections are frequently missed or diagnosed late.
There are two main ways labs look for it. The first is examining the sample under a microscope using special staining techniques that make the parasite visible. The most reliable approach uses ultraviolet light, under which Cyclospora naturally glows blue or green, but not all labs have that equipment. The second approach uses a DNA-based test called PCR, which looks for the parasite's genetic characteristics rather than trying to spot it visually. Some broader panels that test for many GI illnesses at once do include Cyclospora, but not all of them do, so a negative result on a general stomach illness panel does not automatically rule it out.
Can someone test negative even if they actually have Cyclospora? Yes. The parasite is shed in stool inconsistently and in small amounts, so a single negative sample does not rule it out. Doctors are advised to test at least three separate stool samples on different days before concluding a result is truly negative. If you have persistent, unexplained watery diarrhea and a first test came back negative, it's reasonable to ask your doctor about additional testing.
How do investigators test produce for Cyclospora, and is that the same as the clinical test? It is a similar concept but a different process, and the two are not interchangeable.
When investigators test produce, they wash the surface of the food and then test the wash liquid for signs of the parasite's DNA. They are not testing the food itself in the way you might imagine. The FDA has an official method for this which was updated relatively recently. The method can detect very small amounts of contamination, as few as five oocysts (the microscopic form of the parasite) on a sample.
Do all labs use the same method to test produce for Cyclospora? No. The FDA has an official validated method (BAM Chapter 19b) that its regulatory labs use, but there is currently no international standard requiring all labs to follow the same approach. The International Organization for Standardization is in the process of developing one, but until it exists, labs in different countries, and potentially different labs within the U.S., may be using approaches with different levels of sensitivity and precision. This makes it harder to compare results across investigations and complicates coordination during international outbreaks.
What does a negative test result on produce actually mean? Testing is one important tool in outbreak investigations, but it works best when samples are collected early and in sufficient quantity. The FDA's validated method for detecting Cyclospora on produce (BAM Chapter 19b) should be specific and scientifically rigorous. When samples are available and tested promptly, results are meaningful.
The challenge in many investigations is not the method itself but the combination of two compounding factors. First, investigators frequently do not yet know which product, if any, to test. Identifying the vehicle requires patient interviews, purchase records, and traceback work that takes time, and until that picture comes together, there is no clear target. Second, by the time a likely vehicle is identified, the implicated product (if food) has often already been consumed or has deteriorated past the point where reliable testing is possible.
When testing is part of a well-coordinated, timely response with a clearly identified vehicle, it is a valuable piece of that larger picture.
What makes identification of a source of a Cyclospora infection difficult? Unlike common bacterial pathogens like Salmonella or E. coli, Cyclospora is a parasite with a more complex biology. The way it reproduces (replicates only inside a human host) makes whole-genome DNA fingerprinting tools unavailable, which means investigators have fewer tools to quickly connect individual cases to a common source or trace them back to a specific food or farm. This is one reason outbreak investigations involving Cyclospora take longer than those involving bacteria. CDC has developed a genotyping tool that can help link cases during an investigation, and it has been used in past outbreaks, but it is still being refined and does not yet provide the same speed or resolution as the whole-genome sequencing routinely used for bacterial pathogens.
Why is it so hard to trace Cyclospora back through the supply chain? Fresh produce supply chains are complex by nature, and that complexity works against fast traceback even when investigators have a strong lead, and it's substantially harder still when they don't. A single bag of salad mix, for example, can combine lettuce varieties from multiple growers, sometimes across different states or countries, that are washed, mixed, and packed together at a single facility. Once commingled, there's no way to separate out which grower's product is in any given bag. Restaurant supply chains add another layer: a single menu item can draw ingredients from multiple distributors, and a chain's locations in one region may not all source from the same supplier.
This complexity is compounded by Cyclospora's biology, which limits nearly every tool investigators would normally rely on. Unlike bacteria such as Salmonella or E. coli, Cyclospora can't be cultured in a lab, which limits how well standard whole-genome DNA fingerprinting techniques work for linking individual cases to a common source. CDC has developed a genotyping tool that can help link cases during an investigation, and it has been used in past outbreaks, but it is still being refined and does not yet provide the same speed or resolution as whole-genome sequencing. Produce testing has its own limitations too, since perishable products are often gone by the time a lead emerges, and even when samples are available, detection sensitivity drops off at low contamination levels. That leaves patient interviews and purchase records as an important piece of the puzzle, but not a substitute for the physical and laboratory evidence that's harder to come by with this parasite. This combination, limited lab tools, limited testing windows, and a genuinely complex supply chain, is why outbreak investigations involving Cyclospora consistently take longer, and are harder to resolve, than those involving bacteria.
Regulatory and Industry
What are the FSMA requirements for Cyclospora prevention? The federal Produce Safety Rule (21 CFR Part 112) doesn't call out Cyclospora specifically, but several of its rules directly help prevent it, mainly because humans are the parasite's only known source. Broadly, the rule focuses on two things: keeping sick workers away from produce, and keeping water sources clean.
On the worker side, farms are required to keep any employee who is sick, or appears to be sick, away from tasks involving produce or anything that touches produce (§112.31). Farms must also train workers on proper hygiene, and toilet and handwashing facilities have to be placed and maintained so they can't contaminate crops, food-contact surfaces, or water sources (§112.32).
On the water side, farms are required to review their water supply every year, looking at where it comes from, how it's used on crops, and whether anything nearby could affect its quality. If that review turns up a concern, farms have to take action to fix it, and they're required to move especially quickly if the concern involves nearby sanitation issues. Water used after harvest, for washing or cooling produce, is held to an even stricter, testable standard.
For more detail on the water-specific requirements, see the questions below.
Are farms required to do anything about their water to prevent this? Yes. Under the FDA's Food Safety Modernization Act (FSMA) Produce Safety Rule, farms that grow fruits and vegetables covered by the rule must meet standards for agricultural water, which is any water used during growing, harvesting, packing, or holding that is likely to contact the produce or surfaces that touch the produce. The core requirement is that all agricultural water must be safe and of adequate sanitary quality for its intended use.
What specifically are farms required to do to check their water? As of a 2024 update to the rule, farms are required to take a careful, documented look at their water supply every year before and during the growing season. This goes beyond simply running a water test. It is a whole-picture review: where the water comes from, how it moves through the farm, how it is applied to crops through irrigation systems, and whether anything nearby could affect its quality. That includes evaluating surrounding land uses such as wastewater treatment facilities, septic systems, and portable or fixed restroom facilities, whether those are located on the farm itself or on neighboring properties. Importantly, if a neighboring property is upstream of a farm's water supply and the farm cannot get information about what that neighbor is doing, the rule expects the farm to account for that uncertainty by treating it as a potential risk rather than assuming everything is fine. Based on what they find, farms determine whether any changes or safeguards are needed, with the goal of catching potential issues before produce ever reaches a store shelf.
What happens if the assessment finds a problem with the water? Finding a potential issue does not mean a farm is in trouble. It means the system is working as intended. When an assessment identifies a concern, farms are required to take steps to address it, and the rule gives them several practical options for doing so. They might repair or upgrade part of the water system, change how water is delivered to crops (for example, switching from overhead sprinklers that spray water onto leaves to drip irrigation that delivers water directly to the roots instead), or treat the water using a method verified to be effective. For concerns tied to sanitation issues on nearby land, the rule asks farms to act on a faster timeline than they would for other types of issues, reflecting how seriously that particular risk is taken.
Are water safety requirements under the rule limited to the growing season, or do they extend to harvest and packing as well? They extend well beyond harvest. Water used for washing, cooling, transporting, or packing produce after it leaves the field is also regulated under the rule, and it is actually held to a stricter standard than pre-harvest water. It must meet a specific measurable microbial quality criterion with no detectable generic E. coli per 100 milliliters of water, and it is subject to testing requirements rather than the assessment-based approach used for pre-harvest water. Water used to make ice that contacts produce and water used for handwashing during harvest activities are also included in these requirements.
Some third-party audit programs go further still on water quality, requiring that water used in post-harvest operations meet potable (drinking-quality) standards rather than simply the regulatory criterion of no detectable E. coli. For a parasite like Cyclospora, where E. coli testing does not directly indicate the parasite's presence or absence, that higher standard provides a meaningful additional layer of protection.
What can growers do to reduce the risk of Cyclospora contamination on their farm? It's important to be direct about something here: there is currently no FDA guidance or validated, Cyclospora-specific protocol that tells growers exactly how to prevent contamination. This is a real gap, not an oversight, it reflects how difficult this particular parasite is to study and detect, something we've noted throughout this page.
What does exist is general Good Agricultural Practices (GAPs), which are believed to reduce risk broadly across many pathogens, though they were not developed or validated specifically against Cyclospora. Beyond that, researchers at the University of Florida have published practical recommendations specifically discussing Cyclospora, offering thoughtful, expert-informed suggestions rather than an established or validated protocol. Prevention of Cyclospora Contamination and Transmission on the Farm (UF/IFAS Extension) and Preventing Foodborne Illness: Cyclospora cayetanensis (USDA/NIFA).
Their key recommendations include the following, though growers with specific questions are encouraged to consult their local university extension service, regulatory contacts, or other qualified technical resources for guidance tailored to their specific situation.
- Know your water sources. Map all water sources on and adjacent to your farm, including nearby sewage systems, septic tanks, and drain fields. After crops are established, avoid using surface water for any activity that contacts the harvestable portion of the crop. Where water quality is uncertain, use potable (drinking-quality) water for washing produce and for any post-harvest activities that contact food surfaces.
- Have a plan for weather events. Flooding and heavy rainfall can move contamination from sanitation infrastructure into growing areas and water systems. UF researchers specifically recommend developing a written corrective action plan for significant weather events before they occur, not after.
- Maintain sanitation infrastructure. Provide sufficient, accessible, and properly functioning toilet facilities for all workers. Use reputable companies for cleaning and maintaining portable toilets and site those facilities away from growing areas and all water sources. Have written corrective action procedures in place for any spills or leaks.
- Train workers thoroughly and in their language. Training materials should be appropriate for workers' native language and background, and should cover proper handwashing, recognizing illness symptoms, not working while sick, and correct use of toilet facilities.
- Avoid untreated manure. Do not use untreated manure as fertilizer on crops eaten raw. If composted amendments are used, follow applicable USDA guidelines on timing and application.
IFPA Actions to Date
What is IFPA doing? IFPA has been monitoring this situation since early July and remains in ongoing, active contact with CDC, FDA, and state health officials in Michigan, Ohio, West Virginia, and Kentucky as the investigation has expanded to a multistate response. We're sharing verified updates with our members as they become available and are working to help make sure our members, our media partners and others have up to date information to understand the actual state of the evidence. We recognize that an active investigation with no confirmed source, combined with seasonal timing and elevated case across the affected states has naturally raised questions and generated significant public attention, and that response is understandable. What we know, we will share. What remains under investigation, we will say so clearly rather than speculate.
Where can I get updates? This page will be updated as new information is confirmed. We encourage the public to rely on verified updates from public health agencies. For deeper technical background on the parasite and its relationship to the fresh produce industry, visit IFPA's Cyclospora resource page. For members with specific questions, IFPA's food safety experts are available.
Media Contact: Media@freshproduce.com
Food Safety Contact: Foodsafety@freshproduce.com