Cyclospora outbreak tracking and reducing your risks as a fruit and vegetable grower

Annalisa Hultberg, Extension educator, food safety 

This article contains updates related to the current multi-state Cyclospora outbreak. Since this is an evolving investigation, updates will be posted as they are available. 

Update 8/13:

As of August 10th, 2026, there have been at least 13,895 laboratory-confirmed cases of cyclosporiasis in the United States. At least 10,455 additional cases of cyclosporiasis may require further investigation and analysis, and it is likely that the number of confirmed cases will continue to rise as more people report symptoms. 

There have been 2 confirmed deaths related to the current outbreaks and over 500 hospitalizations.

It is very likely that more than 1 outbreak is happening at the same time. The only produce item that has been publicly identified as a potential source of illness is iceberg lettuce from central Mexico.  

What should you do as a farmer? The current outbreaks are almost certainly related to water, either irrigation or wash water, used during the production or processing of fruits and vegetables. Continue to test all water used on your farm for the presence of E. coli, which will indicate the presence of fecal contamination.

See the end of this article for more information related to talking with your customers.

Update 7/20:

• On 7/19, after reviewing the results from recent sampling efforts, the FDA announced that the previously confirmed positive test of Cyclospora linked to the current 5-state outbreak from Taylor Farms was a false positive.
• While there are not currently any documented positive tests, this does not mean that the produce causing illnesses definitely did not come from Taylor Farms in central Mexico. It just means that a positive test confirmation is not present. The epidemiological studies that are following ill consumers continue to indicate that Taylor Farms lettuce from central Mexico is the likely source of the illness, though the case is evolving as more information comes in. 
• Taylor Farms de Mexico is recalling iceberg lettuce sourced from central Mexico from the U.S. market “because it has the potential to be contaminated with Cyclospora.” 
• For a complete list of lot numbers and recall information, see this recall notice from the company
• It is important to remember that locally grown lettuce is not impacted by the recall, and when grown using Good Agricultural Practices, including using tested and safe sources of water for irrigation, is not a risk to consumers. 
• Local growers use well water, which is very unlikely to contain the Cyclospora parasite. For tips on talking with consumers about your products, see the section at the end of this article. 

Update 7/17: 

The FDA has indicated that the likely source of the Cyclospora outbreak is shredded lettuce served at Taco Bell locations. This information is from the CDC.

The source of the contaminated food is likely:

• Shredded iceberg lettuce served at Taco Bell locations in 5 states
• More than 1,644 sick people in this outbreak reported eating at Taco Bell locations in 5 states.
• FDA's traceback investigation has identified a single supplier of iceberg lettuce from Mexico used by these Taco Bell locations.
• FDA is working directly with the supplier to determine if contaminated shredded iceberg lettuce went to other places

Original article:

Over 5000 reported illnesses and 80 hospitalizations have been attributed to Cyclospora as of July 16. Cyclospora is a microscopic parasite that causes an intestinal illness called cyclosporiasis. This parasite is implicated in a major nationwide outbreak of foodborne illnesses, likely associated with the consumption of fruits and vegetables. Understand how basic Good Agricultural Practices can reduce risks on your farm, especially related to your water sources, and protect your crops and consumers from this parasite (and other illness-causing hazards such as bacteria and viruses).

What is Cyclospora?

Cyclospora is a microscopic protozoan that you cannot see without magnification, smell, or taste. It has been a known yet relatively uncommon cause of foodborne illness in the U.S. for decades. It differs from E. coli, Salmonella, and other bacterial causes of foodborne illness, as it is relatively rare in many growing environments, since most farm environments and water sources (thankfully) lack the presence of human sewage that could contain this parasite. It is not endemic to the US, so outbreaks have historically been related to produce imported from countries where Cyclospora is common in the population. It can be present in the US as well, when people travel to other countries and contract the parasite.

We do not know what produce items are linked to the current outbreak or where they were grown, but previous Cyclospora outbreaks have been linked to fresh produce such as raspberries, cabbage, basil, cilantro, parsley, broccoli, snow peas, sugar snap peas, and leafy greens. The produce that has been implicated in past outbreaks has been grown both domestically and internationally, though many cases have originated outside of the US. Many of these produce items that have caused illnesses are generally eaten raw and lack a kill step, which would kill the parasite if present. These produce items are also difficult to clean well, and may not be washed at all by the consumer.

Symptoms of Illness

Infected individuals often show signs of illness about a week or more after consumption, making it difficult to trace this foodborne illness, since many people do not recall the foods they ate for weeks prior.  Cyclospora usually causes watery and explosive diarrhea, with frequent bowel movements. Other common symptoms include loss of appetite, weight loss, stomach cramps/pain, bloating, increased gas, nausea, and fatigue. The good news is that most people who get sick fully recover without lasting health effects, though some people face a relapse of symptoms for years. 

How does Cyclospora contaminate fresh fruits and vegetables?

This parasite is most often introduced into surface water from human sewage, such as during combined sewage overflow events, when untreated wastewater is discharged into bodies of water. It can enter waterways if septic systems, outhouses, or other restroom facilities are not properly contained, and if the people using them are infected with the parasite. It can be in rivers and streams, ponds or other water that is vulnerable to runoff. This is why surface water sources are more risky to use on your farm. 

If the contaminated water is used to irrigate or wash vegetables, the people who eat the fruits and vegetables can become ill if microscopic amounts of the parasite remain on the produce. The parasite does not come from wildlife feces, only from human feces.  

Reminder: this parasite does not transfer from person to person, because the Cyclospora parasite needs time (days or weeks) in the environment after being passed in feces to become infectious. So it is different from Covid or other viruses that can easily spread from human to human.

What can farmers do to reduce their risks related to Cyclospora?

Here are some of the most important steps you can take to reduce your risk of transmitting this parasite or other microbes that can cause illness via your fruits and vegetables:

Water

Since this parasite is most often introduced to the growing environment via water, use only clean and tested water on your farm for irrigation, washing produce, cleaning surfaces and handwashing.  If you use well water, test it annually for the presence of generic E. coli. If E. coli is present in the water, it is a good indicator that human feces are present. Where there is human feces, there may be other contaminants, such as Cyclospora, Listeria monocytogenes, Cryptosporidium, or Salmonella that can cause illness.

For more information on water testing, see this website. 

Also read this blog post with a "script" for talking to water testing labs. 

If you use surface water like rivers, ponds or streams as a source of water for irrigation, know that this is a risky practice, as this water is vulnerable to contamination from human or animal feces.  You can reduce the risks in the following way:  

• If you use surface water to irrigate, consider not using this water on produce that may be consumed raw, such as greens, broccoli, tomatoes, melons, and peppers. Instead, use this water to irrigate produce like winter squash, potatoes, or other items that are generally cooked. 
• If you use surface water, test it multiple times throughout the season for generic E. coli 
• If you you use surface water, use a drip line system to apply the water to the produce that grows above the ground.
• This will reduce the risk substantially, as the water will not touch the portion of the produce that will be consumed.

Other important steps farms can take

• Exclude sick workers from handling fresh produce. Since Cyclospora spreads through human fecal matter, people with symptoms of vomiting or diarrhea should not handle produce on your farm. This is a best practice to reduce the spread of other bacteria and viruses that can cause foodborne illnesses on your fresh fruits and vegetables as well, like E. coli, Salmonella and Norovirus.
• Clean and sanitize totes, tools and any surfaces that might touch food regularly to reduce cross-contamination. Regular cleaning and sanitizing of food contact surfaces and tools is a good idea to reduce the build up of biofilms that can trap bacteria, viruses and parasites, if present. 
• Wash hands with warm water and soap for at least 20 seconds before handling produce, after using the restroom, before and after eating, and other times your hands might be contaminated. 
• Hand sanitizers will not work to kill this parasite. 

What should consumers do to reduce their risks related to Cyclospora?

For more information, see the FDA page on Cyclospora here. 

• Rinse all produce thoroughly at home under running water, including before you peel them. 
• It is important to know that rinsing produce will likely reduce the amount of Cyclospora, but it will not eliminate it. Produce with many bumps or surface area, like leafy greens, herbs and melons, may be particularly difficult to wash. The parasite (and many bacteria) can be stuck on tiny bumps on the produce, and be impossible to fully wash off. 
• Additives like vinegar or produce washes will not be more effective than running water for rinsing your produce. Do not add soap or anything else that may contaminate your fresh produce and not intended to be consumed. Household bleach is not effective against this parasite, so do not use bleach in your rinse water. 
• Discard outer layers of produce, since irrigation water may often land on that part of the produce.  Peel produce with a rind. 
• Use a clean vegetable brush to scrub firm produce. 
• Be cautious with pre-washed or pre-cut produce like bagged produce. Commercial washing processes may not be sufficient to remove the parasite. 
• If possible, cook produce. Cooking to 158 degrees is the only guaranteed method to kill the parasite, if present. 

What should I tell my customers? 

If you receive questions about the Cyclospora outbreak from customers:

• Remind your customers that you use tested well water (if you do) for rinsing produce and irrigation, and that you always have. Therefore, your produce has a very low probability of being contaminated with this parasite. 
• Remind them that contaminated water is most likely the culprit of this current outbreak, since it has been in the past, and that you have taken steps to understand the risks associated with your farm's water and reduce those risks in accordance with industry standards. 
• Remind them that Cyclospora comes from water contaminated with human feces. If there is no reason to think that people who are ill with the parasite have been on your farm, or polluted your farm's water, you do not have any reason to think that Cyclospora would be on your fresh produce. 

The good thing is that Good Agricultural Practices that many farmers learn about and use on their farms are very useful in times like this, since you can use your food safety plan and policies to assure consumers that fresh produce is likely healthy and safe and they should not avoid eating fresh foods.