LOS ANGELES, July 19 (Xinhua) -- The U.S. Food and Drug Administration (FDA) said Sunday that a previous test result indicating the presence of the cyclospora parasite in lettuce samples from Taylor Farms should be considered a false positive.

This photo taken on July 17, 2026 shows a Taco Bell store in San Gabriel, Los Angeles County, California, the United States. (Photo: Xinhua)

As of Sunday, there were no confirmed positive sample results for cyclospora, it said, adding that the investigation remains ongoing.

The finding came one day after the agency said a sample of shredded iceberg lettuce supplied by Taylor Farms tested positive for the parasitic illness that has sickened thousands of people in the states of Indiana, Kentucky, Michigan, Ohio and West Virginia.

The California-based lettuce supplier said Sunday that the FDA apologized to it, noting that it had completed a voluntary recall of iceberg lettuce from central Mexico out of an abundance of caution based on "initial information provided by health officials."

As of Saturday, the U.S. Centers for Disease Control and Prevention reported more than 1,644 cases of cyclosporiasis across the country, with 94 hospitalizations and no deaths.