This summer's cyclospora outbreak that prompted concerns about eating iceberg lettuce appears to be winding down, according to federal health officials.
The number of new cases nationwide is dropping even as the number of cases reported in California grew exponentially over the summer.
California is not one of the outbreak states, although 313 confirmed and probable cases of cyclosporiasis were reported in the state between May 1 and Aug. 1, according to the California Department of Public Health.
Of those, 56 were classified as domestic cases, meaning the patients had no recent international travel. Nineteen of those 56 reported traveling outside California but elsewhere in the United States. Fourteen people were hospitalized and no deaths were reported.
The Food and Drug Administration said in an update last week that it "remains confident" all recalled iceberg lettuce related to the multistate cyclospora outbreak is off the market. The best-by dates on the recalled products have passed, and the products should no longer be available in stores and restaurants.
Cyclospora is a microscopic parasite that causes cyclosporiasis, a gastrointestinal illness whose most common symptom is watery diarrhea. Cases linked to the iceberg lettuce outbreak reached 11,458 in 20 states as of Aug. 27, according to federal health officials. Nearly 500 people have been hospitalized, and two people have died, both in Michigan.
Three new states were added in the latest update. The outbreak states are Arkansas, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Massachusetts, Michigan, Missouri, Nebraska, New Hampshire, North Carolina, Ohio, Oklahoma, Pennsylvania, Tennessee, Texas and West Virginia.
The California Department of Public Health said California is not currently experiencing an outbreak of cyclosporiasis. The department said the increase in cases follows a normal seasonal pattern and is mostly associated with international travel. The state's public health department website indicates that the contaminated iceberg lettuce linked to the outbreak affecting Midwestern and eastern states was not distributed in California. However, in late August, the FDA announced that contaminated lettuce recalled by Taylor Farms after it was linked to a widespread cyclospora outbreak may have also been distributed to California.
The true number of people sickened in the multistate outbreak is likely higher than the number reported to health officials because many people recover without medical care and are not tested for Cyclospora, according to the CDC.
Cyclosporiasis infections typically increase during the spring and summer months. The 2026 cyclosporiasis season began May 1, according to the CDC's national surveillance data. People can become infected by consuming food or water contaminated with human feces containing Cyclospora, according to the CDC.
The CDC and FDA are continuing their investigation into the cyclospora outbreak, which has been linked to iceberg lettuce sourced from central Mexico and recalled by Taylor Farms de Mexico. The FDA's traceback investigation identified the company as the supplier of shredded iceberg lettuce served at Taco Bell locations where people became sick.
Taylor Farms de Mexico recalled all iceberg lettuce sourced from central Mexico on July 17. The recall also included Marketside-brand iceberg lettuce products sold at certain Walmart stores.
Officials haven't declared the outbreak over, but health experts say it's generally safe to eat iceberg lettuce again as long as it's not tied to the initial recall.
"In terms of the risk to consumers now, if today for dinner you wanted to go out and eat a salad, you're pretty safe from cyclospora at this point, as far as we know," Matthew Moore, an associate professor of food science at the University of Massachusetts Amherst, told CNN.
Dr. Colleen Kraft, a professor of infectious diseases at Emory University School of Medicine, told CNN she's "comfortable with people eating iceberg lettuce that is currently being sold."
"I would distinguish between the specific recalled product and iceberg lettuce as a category," Kraft told CNN. "The implicated lettuce is no longer expected to be on the market. There is always some baseline risk associated with eating raw produce, but there is not currently a recommendation to avoid all iceberg lettuce because of this outbreak."
California's latest figures differ substantially from the snapshot state health officials provided earlier this summer, although the two sets of numbers cover different reporting periods and are not directly comparable.
In a July 14 news release titled "California Not Among States Experiencing Increased Cyclosporiasis Cases," CDPH said California had reported 41 provisional cases from January through June, compared with 80 during the same period in 2025.
At the time, CDPH said there were no known local outbreaks and no California cases were known to be linked to outbreaks affecting other states.
CDPH's current data show 313 confirmed and probable cases from May 1 through Aug. 1. The department cautions that the figures are provisional and expected to change because clinical, laboratory and epidemiological investigations can delay reporting.
A case refers to an individual illness, while an outbreak generally refers to a group of illnesses linked by public health investigators to a common source or exposure. California can therefore report individual cases of cyclosporiasis without being considered part of the current lettuce-linked outbreak.
Federal information about whether recalled lettuce might have reached California also changed during the investigation. An Aug. 13 FDA update listed California among several jurisdictions where recalled products may have been distributed further, although distribution in California had not been confirmed.
California is no longer included among the confirmed or possible additional distribution locations in the FDA's current outbreak information, while CDPH says the implicated lettuce was not distributed in California.
Rinsing lettuce and other produce under the faucet may reduce the risk of cyclospora and other foodborne illnesses, but washing alone cannot guarantee that the parasite is gone, federal health officials caution. And there's a right and wrong way to wash produce.
The FDA recommends discarding the outer two or three layers of leafy greens, then rinsing the remaining leaves thoroughly under clean running water. Do not use soap, bleach or commercial produce washes. Cyclospora can resist chlorine-based sanitizers, and soap or detergent can be absorbed by porous produce and make people sick.
The advice extends well beyond lettuce. Previous U.S. cyclospora outbreaks have been linked to raspberries, cabbage, basil, cilantro, parsley, broccoli, snow peas, sugar snap peas and other leafy greens. The parasite can settle into the folds, crevices and rough surfaces of produce, making it difficult to wash away completely.
The CDC recommends washing hands with soap and water before and after handling raw produce, removing bruised or damaged areas and rinsing all fruits and vegetables before eating, cutting or cooking them. That includes melons, cucumbers and other produce with peels that will not be eaten because a knife can carry contaminants from the surface into the flesh. Firm produce should be scrubbed with a clean produce brush.
Berries and delicate herbs should be rinsed gently under running water rather than soaked, which can spread contamination through the water. Produce labeled "prewashed" or "ready to eat" generally does not need another rinse, although the FDA warns that commercial washing may not remove cyclospora.
Cooking produce to at least 158 degrees is the most reliable way to kill the parasite. Cut, peeled or cooked fruits and vegetables should be refrigerated within two hours.
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