Expert Insight: Understanding This Year's Cyclosporiasis Outbreak and Food Recalls

Cyclosporiasis Outbreak Update

The Centers for Disease Control and Prevention (CDC) has confirmed 19,595 domestically acquired cases of cyclosporiasis since May 1, 2026, as it continues to report a multistate outbreak linked to iceberg lettuce. The agency says it is also aware of more than 6,149 additional cases that have not been laboratory-confirmed or are still under investigation.¹ Among the confirmed domestic cases reported between May 1 and September 8, 1043 people have been hospitalized and 2 have died. Patients ranged in age from 1 to 98, with a median age of 46, and 56% were female. The median date of illness onset was July 8, with cases ranging from May 1 to August 30. All of these individuals reported eating food in the US and had no international travel in the 14 days before falling ill.¹

Cyclosporiasis is a gastrointestinal illness caused by the microscopic parasite, cyclospora, typically spread through contaminated food or water.

“Cyclospora is not a bacteria…Many of our foodborne illnesses we think of them as bacteria. We can handle them in a little bit different way. Their control and prevention are certainly different,” explained Lynette Johnston, PhD, assistant professor and food safety extension specialist, NC State University. “Cyclospora is definitely a hardier organism that is harder to control. The other thing is we know less about this organism…It's one that we know to contaminate food and water, and that infection even itself, is a little bit different than bacteria, causing watery diarrhea that can last anywhere from one to two weeks.”

Michigan has been the state most affected by the outbreak. As of September 6, health officials reported the state's cyclosporiasis outbreak has now reached 14,718 total cases, with 366 reported cases resulting in hospitalization as of September 3, 2026. Two deaths have also been identified as part of the outbreak; according to medical records, both individuals had significant underlying health conditions that may have been impacted by cyclosporiasis and dehydration.²

Notably, both Michigan deaths occurred in people who became ill before the FDA's July 17 voluntary recall of iceberg lettuce tied to the outbreak, and no further details will be released about these two cases. Health officials emphasize that cyclosporiasis is generally not a life-threatening illness, and death from the infection remains uncommon in the United States.² It is a nationally notifiable disease and reportable in 47 states, the District of Columbia and New York City.¹

Source of Outbreak

The current outbreak is centered on a recall issued July 17, when Taylor Farms pulled iceberg lettuce sourced from central Mexico that had been sold at retail stores, served in restaurants, and distributed to food service customers.

“We definitely see a decline due to that outbreak,” Johnston said. “So the good news there is that one, we do see cases declining from that…Two, we're past the point of any new recall because that particular lettuce, because of that recall, we should not be seeing any of that lettuce on the market anymore.”

CDC, the FDA, and state health officials are jointly investigating the outbreak, and it has contributed significantly to this year's case increase. Because case numbers are running well above the same period in 2025, CDC has been publishing surveillance updates weekly rather than at its usual pace.¹

CDC cautions that its figures likely undercount the true scale of the outbreak. The agency estimates roughly a six-week lag between when someone gets sick and when their case is reported. Some people who recover without seeking medical care are never tested for cyclospora and so never appear in official tallies. State health departments, CDC notes, may also have more current information about cases in their own jurisdictions than what shows up in federal data.¹

Cyclosporiasis cases typically climb during the spring and summer, with the US outbreak season running from May 1 through August 31, though clusters have appeared outside that window in past years. CDC and other agencies continue working to refine molecular tools that can more precisely link cases to a common source.¹

The Prevention Challenge

With the cyclospora outbreak, Johnston notes the difficulties in washing lettuce in trying to prevent infection.

“Cyclospora is much more resistant to our normal sanitization procedures….We always say it's best practice to wash your fresh produce under running water, but we have to remember that with this organism, that water rinse is really not going to do much to remove cyclospora,” she said. “For whole lettuce, you could remove the outer layers, and that is a good practice to conduct to sort of minimize your risk of Cyclospora.”

Food Recalls

Although there seems to be a lot of recalls in the news this year, Johnston provides some context for them compared to previous years.

“When we look at the raw recall counts this year, it isn't actually shaping up to be dramatically higher than recent years. Some tracking even suggests it could actually come in a little bit lower than last year,” Johnston said.

She explains there are a few reason this year feels especially bad including the size and scope of the cyclosporiasis outbreak, better overall food surveillance detection that is naming outbreaks, and lastly, affected foods may cascade into separate recalls when a singular source of food, may be used in multiple products.

Johnston points out it is important to separate the food recalls from the outbreaks.

“The bottom line here is I think that more recalls isn't automatically a bad sign. It can mean that the system is catching more. But I will say, the severity of what we've seen this year, especially with cyclospora, we've seen a number of cases dramatically increase this year. That's certainly a real trend worth taking seriously, separate from that raw recall count.”

This is a 2-part interview with Johnston. In the next episode, she will discuss the food surveillance protocols and technology in place to help diagnose outbreaks and identify the source(s) of these food-borne pathogens.

References

1.Surveillance of Cyclosporiasis. CDC. September 8, 2026. Accessed September 11, 2026. https://www.cdc.gov/cyclosporiasis/php/surveillance/index.html

2. Infectious Disease Outbreaks. Michigan Health and Human Services. September 8, 2026. Accessed September 11, 2026.
https://www.michigan.gov/mdhhs/keep-mi-healthy/infectious-diseases/infectious-disease-outbreaks