Uncovering the culprit of the Nanning high school food poisoning case: crispy fish sticks

The nutritious lunch provided by the central kitchen of Nanning High School on March 13 caused teachers and students to experience allergic reaction symptoms such as nausea, vomiting, facial flushing, itching, and rash after consuming it. After investigation by the Nanning City Health Bureau, samples of the lunch that day were sent to the Southern District Management Center of the Food and Drug Administration of the Department of Health for testing. The results showed that the culprit was "crispy fish strips."

The investigation report on the collective food poisoning case among students of Nanning High School in Tainan has been released. The culprit was histamine poisoning caused by crispy fish strips. Patients will experience symptoms such as nausea and facial flushing.

The histamine content in fresh fish is usually below 10ppm. The Southern District Management Center tested "crispy fish strips" and found histamine as high as 3310ppm. The causative substance was histamine toxin and the cause food was crispy fish strips. This was a case of food poisoning caused by histamine.

Stale fish and shellfish often cause histamine food poisoning. Symptoms of poisoning usually appear within 0.5 to several hours after consumption. The earliest skin symptoms include facial flushing, red rashes, itching, etc.; gastrointestinal symptoms include nausea, vomiting, abdominal pain, etc.

The poisoning dose varies greatly depending on individual constitution. People with allergic constitutions are more susceptible to poisoning. Generally speaking, poisoning may occur when the histamine content exceeds 1000ppm. Once fish produce histamine, it is not easy to destroy or reduce the content after heating.

To prevent histamine poisoning, fish should be kept in a frozen or refrigerated state from the time they are caught to the time they are sold to consumers. Histamine is heat-resistant, so if the fish is found to be not fresh, it should be discarded. Do not have the misconception that heating can prevent poisoning.