A cluster of Histamine Fish Poisoning associated with the ingestion of tuna

Histamine fish poisoning, also known as scombroid poisoning, arises from the improper handling and refrigeration of scombroid fish that contain naturally occurring histidine such as tuna, mackerel and swordfish. Histidine is converted to histamine when these fish inadequately chilled. Histamine fish poisoning is generally associated with levels greater than 500 mg/kg but poisonings have been observed at lower levels (e.g. >200 mg/kg). European legislation states that scombroid fish species should be tested for the presence of histamine and mean values should be < 100mg/kg. The authors report an outbreak of probable histamine fish poisoning in three individuals following ingestion of tuna. The tuna was bought in a local store. It was cooked and eaten by the 3 cases at home for their evening meal. Symptom onset occurred between 30 minutes and two hours after ingestion and included flushing, facial/lip swelling, an itchy rash and palpitations. All three cases attended the Emergency Department (ED) requiring oral or Intravenous (IV) anti-histamine and/or oral steroids and IV fluids. Fortunately, all cases recovered fully and were discharged from the ED. The public health actions that were taken, crucially included rapid coordination with the Environmental Health Service (EHS). Temperature control is the crucial step in preventing histamine fish poisoning. The Food Safety Authority of Ireland and the Irish Sea Fisheries Board highlight the importance of proper handling and chilling of fish from time of catch through to transportation, processing, storage and distribution. This report highlights the importance of timely and coordinated public and environmental health responses to histamine fish poisoning cases. National Clinical Guidelines are currently being developed in conjunction with the Irish Association for Emergency Medicine (IAEM) on the Management of Histamine Fish Poisoning/Histamine Poisoning in Adult Patients. KEY MESSAGES: • Environment and Health. • Food governance.