FDA Says Test Was a False Positive in Cyclospora Investigation
- FDA determined initial positive Cyclospora test was a false positive, but recall remains in effect
- Epidemiological evidence and product tracing link outbreak to Taylor Farms de Mexico iceberg lettuce
- Consumers should throw away recalled lettuce and avoid it at restaurants if source is unknown
The Food and Drug Administration has updated its investigation into a multistate Cyclospora outbreak linked to recalled iceberg lettuce. While one laboratory test initially suggested contamination, the agency later determined that result was a false positive. Even with that correction, federal health officials continue to warn consumers not to eat certain recalled lettuce products because the investigation remains active.
What Changed in the FDA Investigation?
The FDA announced that experts reviewed the original laboratory results and determined the positive test for Cyclospora did not accurately detect the parasite. As a result, the agency removed that test result from its public updates.
Officials stressed that the revised finding does not change the overall investigation. The FDA said epidemiological evidence and product tracing continue to point toward recalled shredded iceberg lettuce supplied by Taylor Farms de Mexico.
Which Lettuce Is Still Under Recall?
Taylor Farms voluntarily recalled iceberg lettuce sourced from central Mexico on July 17. The recall includes select Marketside branded iceberg salad and shredded lettuce products sold at Walmart with best by dates from July 18 through August 3, 2026.
The recalled lettuce also reached restaurants and food service locations across several states. The FDA continues working with the company to remove affected products from the market.
What Consumers Should Do
Health officials continue to recommend throwing away any recalled lettuce. They also advise cleaning containers, refrigerator shelves, and kitchen surfaces that may have touched the product.
If you order a salad at a restaurant, ask where the iceberg lettuce came from. The FDA says consumers should avoid recalled lettuce if the source cannot be confirmed. Taco Bell has also stopped using lettuce from the identified supplier.
What Is Cyclospora?
Cyclospora is a parasite that can cause an intestinal illness known as cyclosporiasis. Symptoms often include watery diarrhea, stomach cramps, nausea, fatigue, bloating, loss of appetite, and weight loss.
Some people also develop headaches, body aches, vomiting, or a fever. Symptoms can last for several weeks without treatment and sometimes return after improving.
Current Outbreak Information
According to the FDA and the Centers for Disease Control and Prevention, the outbreak remains under investigation. Officials have confirmed more than 1,600 illnesses connected to the five state outbreak, including dozens of hospitalizations. No deaths have been reported.
The investigation currently focuses on illnesses reported in Indiana, Kentucky, Michigan, Ohio, and West Virginia. However, recalled products were distributed to many additional states, including Georgia, Florida, Texas, North Carolina, South Carolina, Virginia, and several others.
The Bottom Line
The FDA’s updated laboratory findings may sound reassuring, but they do not end the investigation. Federal health officials continue to advise consumers to avoid recalled iceberg lettuce while they gather more evidence.
If you have recalled products at home, throw them away immediately. Anyone who develops symptoms after eating recalled lettuce should contact a health care provider for testing and treatment. The FDA says it will continue providing updates as new information becomes available.
