Occurrence: formed when bacteria grow on histidine-foods such as tuna and mackerel but also in aged cheese and wine.

Symptoms: burning sensation in the mouth, skin redness, itching, headaches, stomach pains, vomiting and diarrhea.

Reason for outbreaks: food has been contaminated by improper storage. Heat resistant even in oven temperatures.

Prevention: good hygiene, the right food at the right temperature. People sensitive to histamines should avoid strong cheese and possibly some wines.