Background: To investigate and control of a collective scombroid-fish poisoning (SFP) outbreak, that took place in Castellón, Spain.
Methods: Description of the outbreak and case-control study in order to identify risk factors. Active surveillance of SFP cases, and inspection of implicated markets. Histamine determination in urine of cases and foods.
Results: During June 1994, 15 cases of SFP were found out, with 12 cases occurred on June, 28 and 29. Five families were affected (attack rate 68.2%). The median incubation period was 45 minutes. Disease symptoms included facial or general flushing, headache, diarrhea, nausea, abdominal pain, and peppery taste. Implicated food was fresh tuna, bought in a hypermarket of Castellón (odds ratio = 26.4, 95% confidence intervals: 1.05-666.8), adjusted by age and sex using logistic regression analysis. Four samples of urine from cases presented histamine concentration above 35 micrograms/l. Three samples of tuna consumed by cases and one sample of tuna from the hypermarket had histamine concentration above a 200 ppm. Considering the situation of risk, remaining suspected tuna was confiscated from the hypermarket. Rest unknown if the descompositions of tuna occurred in the hypermarket or during capture and distribution.
Conclusions: SFP was caused by fresh tuna ingestion with epidemiologic and analytic confirmation. Determination of histamine in urine of patients could permit to confirm SFP.