Making sense of the Cyclospora outbreak(s)

The CDC has been silent for more than a week now on the status of the Cyclospora outbreak linked to lettuce supplied by Taylor Farms de Mexico.

As of July 24, 2026, the agency has confirmed what it describes as “at least 1,947” cases, including 98 hospitalizations, in nine states.

It’s still unclear when this outbreak actually began. In its initial announcement on July 14th, the CDC cited an onset date of June 22, 2026. That onset date was changed three days later. It was pushed back almost six weeks to May 13, 2026.

On July 24th, the CDC quietly changed the onset date back to June 22, 2026, removing more than 200 Michigan cases from its total in the process.

As a result of the CDC having cut six weeks from the front end of the outbreak, the agency’s timeline curve (the Epi Curve) took on a very unusual appearance. Instead of a typical build-up of cases, the outbreak appears to begin two days before the daily case count reaches its peak, tapers off, and then builds a second wave.

Outbreak timeline versus lettuce distribution

On July 17, 2026, Taylor Farms de Mexico recalled all iceberg lettuce sourced from central Mexico. The shredded lettuce was distributed from June 29th thru July 16th to 27 states.

On average, it usually takes about a week (range of 1-14 days) for someone who has been infected with Cyclospora to show symptoms. Any illness arising on or before July 1st (to use a very conservative timeframe) would not be due to consumption of the recalled shipment.

Bill Marler did some excellent reporting on just this point earlier today in his post on Food Poison Journal.

The CDC versus the states

In the absence of frequent and substantive updates (and explanations) from the CDC, it is helpful to turn to the various states for more information.

In his weekend wrap-up, Marler reports just under 21,000 total Cyclospora cases, based on data supplied by individual states. This number includes both domestic cases and those acquired as a result of international travel. Because various states report at different intervals and some do not differentiate between confirmed and probable cases, it is difficult to correlate the state numbers directly with CDC Cyclospora surveillance totals.

What is more instructive in understanding the timeline of the outbreak are the Epi Curves posted by a few states. Again, these curves do not differentiate between cases linked to Taylor Farms lettuce and other cases, nor do they always differentiate between domestic and international cases or between confirmed and probable cases.

Nevertheless, one thing stands out clearly. Every single one of these state charts show a slow build-up to a peak. Not one of them starts at the peak of the outbreak.

Iowa

The Iowa chart presents lab-confirmed cases only, by week of onset. Notice the number of cases start to climb around mid-May. As of July 24th, the CDC has not included Iowa in its Taylor Farms lettuce outbreak data.

New York City

New York is not one of the states that received the recalled lettuce. However, Taylor Farms supplied that lettuce to consignees in New Jersey, just across the river. New York City has experienced 511 cases of Cyclospora infections since May 1, 2026 (as of July 27th). This chart is based on date of diagnosis (rather than onset of symptoms) and displays the data by week.

North Carolina

The source of North Carolina’s 718 Cyclospora illnesses is still very much a mystery. Parsley and cilantro consumption have been mentioned as possible factors.

Oklahoma

Oklahoma is one of the nine states identified by the CDC as being part of the Taylor Farms outbreak. The state’s Epi Curve is color-coded to differentiate between domestic and international cases and is accompanied by a table that provides some demographic depth to the state’s reporting.

West Virginia

Also one of the nine Taylor Farms outbreak states, West Virginia’s outbreak onset was later than the other states, starting in the latter part of June 2026 instead of in May.

The unanswered questions

When will the CDC next update its outbreak reporting? Will it change the starting date for the Taylor Farms outbreak yet again?

Where did the prior shipments of Taylor Farms lettuce go? The recalled product was not the first shipment of lettuce to reach the United States. This is the sort of question the FDA’s Traceability Rule was meant to answer. That rule was due to come into force on January 20, 2026. It would have required companies to maintain and share the sort of records that are critical to tracing contaminated product both to its source and to its destination. Enforcement of that rule was put on hold by Congress until July of 2028.

Where did the Cyclospora contamination originate at Taylor Farms de Mexico? Was it in the irrigation water? The processing water? How did it enter the water supply?

Cyclospora can remain viable in the environment for weeks or even months under the right conditions. Can the wastewater treatment facilities in the various cities and rural areas affected by the Cyclospora surge handle the pathogen load? Are municipal water treatment facilities able to ensure safe drinking water in the affected parts of the country?

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OPINION: CDC, FDA flub Cyclospora investigation, surveillance

Cyclospora cayetanensis is not an easy pathogen to deal with. It cannot be grown in the lab. It cannot be studied in lab animals. It cannot be inactivated by the chemical treatments that kill bacteria.

People become infected by eating contaminated food or drinking contaminated water. The pathogen takes up its home in the lining of the intestines, multiplies, and is shed in an inactive form (oocysts) in feces. Human feces. Over a period of days, the oocysts self-fertilize through asexual or sexual reproduction and become embryos capable of infecting their next human victim.

Cyclospora does not multiply outside of a host animal. In the case of C. cayetanensis, that host—the only host—is the human body.

For a field crop such as iceberg lettuce to be contaminated with Cyclospora, it must have come into direct contact with human feces contained either in irrigation water or in fertilizer or soil amendments.

CDC’s slips are showing

The CDC’s reporting of both the Taylor Farms lettuce outbreak and of the country-wide surge in Cyclospora reports has been slipshod and unclear.

When the CDC posts a new outbreak investigation notice, the information usually includes both a map showing the distribution of outbreak cases by state and what is called an Epi Curve—a chart that tracks the case reports by date of illness onset. Both of those visual aides are accompanied by data tables.

The CDC posted its initial notice of a Cyclospora outbreak on July 14, 2026. The notice indicated the number of cases confirmed to be part of the outbreak, and the four states where cases had been confirmed, but did not offer either a breakdown of cases by state or an Epi Curve. Instead, the notice simply advised that the earliest outbreak victims reported becoming ill on June 22, 2026.

In its July 17th update, the CDC added a case distribution map, updated the number of states to five from four, increased the number of confirmed cases to 1,644, and modified the earliest illness onset date to May 13, 2026. There was still no Epi Curve included with the update.

It was July 24th before the CDC finally added an Epi Curve to its outbreak investigation notice. They also updated the number of confirmed cases to 1,947 and added four more states to the outbreak case map. The July 24th notice also modified the illness onset date range once again, advancing the earliest illness onset from May 13th to June 22nd (tip of the keyboard to Bill Marler for pointing out this date discrepancy).

In doing so, the CDC removed at least 210 cases from the tally (Michigan dropped from 1,141 to 931). We don’t know how many more cases were removed, as we do not have an Epi Curve that shows the number of cases by onset date between May 13th and June 22nd.

Unusual Epi Curve

This is the Epi Curve that the CDC posted on July 24th. Notice two things: (1) the curve begins right near a peak in case numbers and (2) there are twin peaks.

For comparison, here are two Epi Curves from previous Cyclospora outbreaks, one from 2019 and the other from 2020

Notice the difference? In both of these older Cyclospora outbreaks associated with leafy greans, there was a build-up of cases. Just a few, at first, then an acceleration to a peak followed by a drop-off.

An outbreak does not burst onto the scene at the peak of its strength.

The twin peaks of the current outbreak also are very unusual. This could be a reporting glitch, with some states lagging in their reports to the CDC. It could be a data collation and analysis lag at the CDC. Or it might be real. We’ll have to wait and see.

Cyclospora surveillance data don’t compute

On July 24th, the CDC also updated its Cyclospora surveillance data, reporting 4,173 laboratory-confirmed domestic cases across 41 states, with an additional 7,400+ cases that are not yet lab-confirmed.

Setting aside the reporting and data-processing lags that have resulted in states posting higher numbers on their own websites than those revealed in the CDC report, there are discrepancies between the data in the surveillance table and the data reported for the Taylor Farms outbreak.

Specifically, the CDC reports a total of “301 to 500” Ohio cases in the surveillance table, but 639 Ohio outbreak cases. Similarly, West Virginia is shown as having reported 42 outbreak cases; yet, only “11 to 30” total cases in the surveillance table.

And while we’re at it, since when does the CDC indicate case-count data by range rather than by actual numbers of cases? The agency knows very well what the case counts are by state. It uses those counts to arrive at the national total. Under normal circumstances, the case-count table shows those individual numbers and NOT a relatively meaningless range, such as the “901 to 2100” cases attributed to Michigan or the “301 to 500” cases shown for Ohio.

What is going on here?

Important surveillance tool tossed in the trash

Once upon a time, the CDC actively searched for incipient Cyclospora infections. The FoodNet program, which covers ten states plus some counties in California, provides active surveillance of the incidence of foodborne diseases in about 16% of the population. In the words of the CDC, “FoodNet is an active surveillance system, meaning that public health officials routinely communicate with more than 700 clinical laboratories serving the surveillance area to identify new infections and conduct periodic audits to ensure that all infections are reported.” (emphasis added).

While FoodNet was not designed specifically to detect foodborne disease outbreaks, it was an important tool to ensure that the systems the CDC relies upon for outbreak detection are functioning as they were meant to.

On July 1, 2025, the CDC changed the reporting requirement for Cyclospora and several other foodborne pathogens from mandatory to optional. Only Salmonella and shiga toxin-producing E. coli remain from the original ten pathogens or conditions that formed the basis for the original FoodNet program.

The FDA’s unforced error

On July 18, 2026, the FDA announced that it had found Cyclospora in a sample of Taylor Farms de Mexico’s shredded iceberg lettuce. One day later, the agency retracted that announcement, explaining that, “Due to the complexity in detection of Cyclospora, FDA laboratory experts re-reviewed the sample results and have concluded that the finding does not represent true amplification and should be considered a false positive.”

What a rookie error!

The sample result should have been reviewed by the agency’s experts before the result was announced, not afterwards. This fumbling of the ball significantly damaged the credibility of the rest of the evidence supporting the FDA’s conclusion that Taylor Farms de Mexico was the source of the outbreak. Instead, it spawned a rash of conspiracy theories on social media. Suggestions that Taylor Farms had twisted arms to get the FDA to retract its lab findings. Hints of payoffs at the most senior levels of the government.

Also feeding those conspiracy theories was the FDA’s apparent reluctance to name Taylor Farms de Mexico as the source of the contaminated lettuce, focussing instead on Taco Bell, the franchise chain named by most of the interviewed outbreak patients as the place where they had consumed iceberg lettuce.

On July 16th, the FDA said that it had identified “…a single supplier of iceberg lettuce from Mexico used by Taco Bell locations where sick people ate before becoming ill,” and was “…working directly with the identified supplier to determine if potentially contaminated shredded iceberg lettuce remains on the market.” It was only on July 17th, the day Taylor Farms de Mexico announced a product recall, that the FDA added the company’s name to the information in the outbreak investigation report on the agency’s website.

What is worse than decimation?

The term “decimation” derives from the old Roman custom of disciplining a military legion by executing 10% of the ranks.

What has taken place within the CDC and the FDA under Trump 2.0 is far worse. The cuts initiated in 2025 by Elon Musk’s so-called “Department of Government Efficiency” were catastrophic. Senior employees who had been promoted into new jobs within the prior two years were ‘probationary’ and therefore able to be terminated with minimal red tape. Similarly, the enthusiastic young blood at the CDC, the interns who had been hired to train as disease detectives, were easy targets for dismissal.

To add to the confusion, the entire communications staff at both agencies was laid off (although some were later ‘invited’ back), and it shows.

It shows in the reduced frequency of outbreak investigation updates on the CDC website.

It shows in the poorly written recall notices on the FDA website.

The old FDA—the agency I once knew and respected—would not have made the rookie mistake of releasing a lab result before it had been confirmed.

The old CDC would not have released surveillance reports and investigation outbreak reports containing multiple errors and/or inconsistencies.

This is what happens when the inmates are given the keys to the asylum’s executive offices.

It’s time to put control of these essential health agencies back into professional hands.

It’s time to change the locks.

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Frozen veggies suspected source of US Listeria outbreak

Frozen vegetables grown and processed in Egypt may be linked to a mysterious outbreak of Listeria monocytogenes infections that erupted in three stages in 2024 and 2025.

According to information obtained by eFoodAlert from the FDA in response to a Freedom of Information Act request, the outbreak was first investigated by the CDC in April 2024 without success. The investigation was reopened in August 2024 when additional cases appeared on the CDC’s radar screen. Again, the investigation was closed without a possible source having been determined.

In June 2025, the CDC reopened the investigation once more after an additional five cases attributed to the same outbreak strain were found. One of those cases occurred in December 2024; the other four from January to May 2025.

Although the outbreak comprised 27 cases overall in 13 states, according to the FDA investigation report, the CDC map provided as part of the report only shows locations for 25 of the cases: Connecticut (1), Florida (2), Illinois (1), Massachusetts (2), Maryland (1), Michigan (1), Minnesota (1), Missouri (1), New Jersey (1), New York (8), Pennsylvania (4), Rhode Island (1), and Virginia (1).

Ages of outbreak victims ranged from less than one to 97 years, with a median age of 72 years. Twenty-five of the victims were hospitalized and one person died. Two of the outbreak patients were pregnant women.

Searching for the source

The FDA did not conduct an official traceback investigation for this outbreak, as the CDC could not supply strong epidemiological evidence for a possible source. However, the agency did conduct a “limited distribution analysis” for two of the cases.

Although many of the details as to the suspected source have been redacted from the investigation report, the FOIA officials left enough breadcrumbs for eFoodAlert to follow.

The recall

The FDA collected records and samples from possible suppliers of the suspect food and, on August 20, 2025, reported positive samples with possible connection to clinical outbreak cases. Eight days later, the CDC advised the FDA that samples collected from one of the suppliers (name redacted in the investigation report supplied to eFoodAlert) was a genetic match for the outbreak strain. Samples collected from the other [unidentified] manufacturer did not match the outbreak strain.

On September 2, 2025, Endico Potatoes Inc. of Mount Vernon, NY recalled two lots of frozen vegetables due to possible Listeria monocytogenes contamination. The recall included one lot each of “frozen peas and carrots” and “mixed vegetables.” According to the Enforcement Report details, the vegetables were imported from Egypt.

In June 2024, the FDA conducted a comprehensive inspection of Endico Potatoes (Inspection ID #1232874) relating to the Foreign Supplier Verification Program. The inspection did not uncover any significant deviations or discrepancies and the results were classified as “No Action Indicated.”

Excerpt from redacted FDA investigation report

The recalled lots of frozen vegetables were manufactured after the last of the outbreak cases was detected, and the recall notice states that no illnesses were reported. Nevertheless, on September 30, 2025, the manufacturer of the frozen vegetables was added to FDA’s Import Alert 99-23, Detention Without Physical Examination of Produce Due to Contamination With Human Pathogens.

The manufacturer and supplier of the recalled vegetables was International Company For Agricultural Production & Processing (ICAPP), headquartered in Cairo, and with production facilities in Ramadan City, Ash Sharqiyah, Egypt. Both the headquarters location and the production plant site were listed in the Import Alert.

On October 22, 2025, the FDA added another supplier to Import Alert 99-23. This supplier, whose samples were positive for Listeria monocytogenes but did not match the outbreak strain, is identified in the Import Alert as Warminskie Zaklady Przetworstwa Owocowo – Warzywnego sp. o.o of Pomorskie, Poland.

Duty to inform

This would not be the first time that frozen vegetables have been linked to an outbreak of Listeria monocytogenes. In 2016, nine people were infected as a result of consuming frozen vegetables produced by CRF Frozen Foods of Pasco, Washington. A Connecticut resident died as a result of the infection, and two other outbreak victims died from other causes.

A separate outbreak between 2015 and 2018 was responsible for at least 47 illnesses and 9 deaths in Austria, Denmark, Finland, Sweden and the United Kingdom. That outbreak was traced to frozen corn and frozen vegetable mixes from a Hungarian freezing plant.

The author(s) of the FDA investigation report acknowledge that frozen vegetables are an “established vehicle” for Listeria monocytogenes, that the suspect products had an extended shelf life, and that contaminated product might still be in consumers’ homes.

The smoking gun (finding the outbreak strain in a sample of frozen vegetables) wasn’t enough for the FDA and CDC to reach a firm conclusion in this case. Instead, they identifed frozen vegetables as the “suspect vehicle” and withheld this information from the public.

Despite knowing that consumers might still be exposed to contaminated product, and despite the likelihood that frozen vegetables were the source of more than two dozen cases of Listeria monocytogenes, including one death, the FDA and the CDC remained silent.

The FDA could have issued an advisory at the time to alert consumers to the risk. This could have been done without naming the importer or the manufacturer.

The FDA should have alerted the public to this hazard, reminding consumers that frozen vegetables are not ready-to-eat products, but must be cooked thoroughly before being consumed.

Transparent opacity

The redacted FDA investigation report is an excellent example of redaction overreach.

The FOIA officer redacted information on the number of outbreak cases and their geographic distribution, even though that information was readily available in the CDC outbreak map included in the same report.

Other information that was redacted even though the information was publicly available included: the identity of the companies added to Import Alert 99-23, the details of the 2016 Listeria monocytogenes in the United States, and the details of the 2015-2018 outbreak in several European countries.

Certainly, proprietary information (e.g., product formulations and supply chain information) should be redacted as a matter of course. But, there is absolutely no justification to redacting information that is readily available to the public from other published sources.

Here is a link to the full redacted FDA Investigation Report as supplied to eFoodAlert in response to our FOIA request.

Cara 1309 report suspected vegs in LM outbreak Download

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