The U.S. Food and Drug Administration (FDA) announced on Friday that inspectors discovered the parasite cyclospora at a Mexican farm that had been previously identified as the source of a significant foodborne illness outbreak. The parasite was located in two specific areas: a wastewater tank and a drainage ditch used in the cultivation of lettuce.

This discovery follows the conclusion of a major health event that the Centers for Disease Control and Prevention (CDC) declared over less than a month ago. That outbreak, which affected 21 states, resulted in nearly 13,000 reported illnesses, marking it as the largest cyclospora outbreak in U.S. history.

Despite the positive identification of the parasite at the farm, the FDA noted that it remains unclear exactly how the lettuce became contaminated. The agency has not yet established a definitive transmission path from the wastewater or drainage areas to the final food product. The announcement serves as a post-outbreak update rather than a warning about an active, ongoing threat to the current food supply, as the CDC has already closed its investigation into the multi-state event.