FDA investigates poisoning linked to yellowfin tuna

The U.S. Food and Drug Administration (FDA) and state health authorities are investigating incidents of scombrotoxin fish poisoning linked to yellowfin tuna, also sometimes called ahi tuna. As a result of this investigation, the FDA has placed Truong Phu Xanh Co. of Vietnam on Import Alert, which provides information to FDA field staff that they may detain the firm’s yellowfin tuna without physical examination. Detained product will not enter the United States unless the importer proves that it meets U.S. food safety standards.

As part of the investigation, the FDA evaluated the firm’s Hazard Analysis and Critical Control Point (HACCP) plans, which detail a firm’s management system to address food safety through the analysis and control of biological, chemical, and physical hazards. Since the FDA’s evaluation of this plan identified deficiencies, the agency asked Truong Phu Xanh Co. to initiate a voluntary recall of all its imported yellowfin tuna with production dates from January 2019 to the present. At this time, the firm has not recalled any product.

The investigation has identified 47 illnesses of scombrotoxin fish poisoning that occurred between August 8 and Oct. 15, 2019.

Throughout the investigation, the FDA and states have also been collecting product samples for testing. Scombrotoxin fish poisoning occurs when fish begin to spoil, resulting in increased histamine levels. Therefore, product samples cannot be linked to case patient samples through Whole Genome Sequencing (WGS) or Pulsed-Field Gel Electrophoresis (PFGE) analysis like for other foodborne illnesses (e.g. Salmonella or Listeria). Instead, samples are tested for decomposition and/or histamine levels. Multiple samples have been collected and analyzed, with positive results for decomposition or high histamine levels in products imported from Truong Phu Xanh Co.

The FDA and state partners collected epidemiologic and traceback information for reported illnesses. As additional epidemiologic and traceback information was collected, the agency and state partners were able to work with companies throughout the supply chain to voluntarily recall implicated product. While recalls were conducted at various points in the supply chain, there may be additional product still on the market that could cause illness.

Ultimately, the coordinated investigation was able to identify Truong Phu Xanh Co. as the common supplier of tuna that was likely consumed by most of the ill people. Because scombrotoxin fish poisoning causes temporary or medically reversible adverse health consequences this incident did not meet the threshold for the use of FDA’s mandatory recall authority.

FDA alert