The FDA initially said that a sample of shredded iceberg lettuce supplied by Taylor Farms had tested positive for the parasitic illness.

The FDA issued an update on the cyclospora outbreak in the United States late Friday, confirming that a single supplier has been identified as the source.

Walmart has removed iceberg lettuce from Taylor Farms for risk of cyclospora. The move comes amid an outbreak investigated by the CDC and FDA.

We still don’t know the source of the outbreak.