The health authorities in the United States continue their investigations to determine the true source of the Cyclospora parasite outbreak causing diarrhea, after retesting samples confirmed that the iceberg lettuce, which was under suspicion, showed no definitive evidence of contamination.

The U.S. Food and Drug Administration (FDA) announced that a thorough review of the laboratory results revealed that the initial positive signal found in one of the lettuce samples was a false positive, confirming that as of July 19, 2026, no confirmed cases had been recorded related to the products that were tested.

The agency explained that detecting the Cyclospora parasite is considered a complex test, prompting laboratory experts to reevaluate the results, revealing that the laboratory signal does not actually reflect the presence of the parasite in the sample.

Despite ruling out the suspected lettuce, investigations are still ongoing in collaboration with local authorities, as additional samples of food and supply chains are being collected in an attempt to identify the actual source of the outbreak.

Taylor Farms had proactively recalled products made from iceberg lettuce grown in Mexico as a precautionary measure after receiving an initial notice indicating a possible link between some of its products and the investigations. However, the company later confirmed that authorities had not found any contamination in its products, which was reinforced by the results of the new tests.

In contrast, U.S. authorities have not issued any updates clarifying the role of the Taco Bell restaurant chain, although initial investigations had linked several cases to the consumption of chopped lettuce used in some of its branches across multiple states, prompting the chain to remove all suspected quantities from the markets and withdraw them from the nationwide supply chain as a precaution.

According to estimates, around 7,000 cases of Cyclospora have been recorded in more than 40 U.S. states, but health authorities emphasize that not all of these cases are related to the current outbreak, as investigations are underway into other independent clusters of infection.

The parasite is typically transmitted through the consumption of contaminated food or water, and is frequently found in leafy vegetables, herbs, and berries. Many cases in the United States are associated with the consumption of imported products or travel to areas where the parasite is prevalent.

The disease causes diarrhea that may last for weeks, along with abdominal cramps, nausea, vomiting, and fatigue, and symptoms may recur if the infected person does not receive appropriate treatment.

Dr. Swapnil Patel, Vice President of Medicine at Hackensack Meridian Jersey Shore Medical Center, advised individuals experiencing diarrhea lasting several days to request a specific test for the Cyclospora parasite, explaining that this test is not typically included in routine analyses.

Diagnosis relies on detecting the parasite's DNA in stool samples, while the disease is often treated with the antibiotic trimethoprim-sulfamethoxazole, which is marketed under several brand names.

The health authorities in the United States continue their investigations to determine the true source of the Cyclospora parasite outbreak causing diarrhea, after retesting samples confirmed that the iceberg lettuce, which was under suspicion, showed no definitive evidence of contamination.

The U.S. Food and Drug Administration (FDA) announced that a thorough review of the laboratory results revealed that the initial positive signal found in one of the lettuce samples was a false positive, confirming that as of July 19, 2026, no confirmed cases had been recorded related to the products that were tested.

The agency explained that detecting the Cyclospora parasite is considered a complex test, prompting laboratory experts to reevaluate the results, revealing that the laboratory signal does not actually reflect the presence of the parasite in the sample.

Despite ruling out the suspected lettuce, investigations are still ongoing in collaboration with local authorities, as additional samples of food and supply chains are being collected in an attempt to identify the actual source of the outbreak.

Taylor Farms had proactively recalled products made from iceberg lettuce grown in Mexico as a precautionary measure after receiving an initial notice indicating a possible link between some of its products and the investigations. However, the company later confirmed that authorities had not found any contamination in its products, which was reinforced by the results of the new tests.

In contrast, U.S. authorities have not issued any updates clarifying the role of the Taco Bell restaurant chain, although initial investigations had linked several cases to the consumption of chopped lettuce used in some of its branches across multiple states, prompting the chain to remove all suspected quantities from the markets and withdraw them from the nationwide supply chain as a precaution.

According to estimates, around 7,000 cases of Cyclospora have been recorded in more than 40 U.S. states, but health authorities emphasize that not all of these cases are related to the current outbreak, as investigations are underway into other independent clusters of infection.

The parasite is typically transmitted through the consumption of contaminated food or water, and is frequently found in leafy vegetables, herbs, and berries. Many cases in the United States are associated with the consumption of imported products or travel to areas where the parasite is prevalent.

The disease causes diarrhea that may last for weeks, along with abdominal cramps, nausea, vomiting, and fatigue, and symptoms may recur if the infected person does not receive appropriate treatment.

Dr. Swapnil Patel, Vice President of Medicine at Hackensack Meridian Jersey Shore Medical Center, advised individuals experiencing diarrhea lasting several days to request a specific test for the Cyclospora parasite, explaining that this test is not typically included in routine analyses.

Diagnosis relies on detecting the parasite's DNA in stool samples, while the disease is often treated with the antibiotic trimethoprim-sulfamethoxazole, which is marketed under several brand names.