RESUMEN
Introduction@#Ciguatera fish poisoning (CFP) is common in tropical and subtropical waters. On 13 November 2015, eight Filipino seafarers from a cargo ship sailing in the Caribbean Sea experienced a range of symptoms after consuming a barracuda. Upon their return to the Philippines, an investigation was conducted to describe the cases.@*Methods@#A case-series was conducted. A CFP case was defined as a previously well individual on the ship who developed at least one gastrointestinal symptom and at least one neurologic manifestation after eating barracuda on 13 November 2015. All cases were admitted to hospital in Manila, Philippines and were interviewed using a standard questionnaire. Urine and serum samples of cases were collected for ciguatoxin (CTX) testing by radiological and receptor-binding assay.@*Results@#Eight of the 25 seafarers on the ship ate the barracuda; all eight met the CFP case definition. The age of cases ranged from 37 to 58 years (median: 47 years) and all were males. Onset of symptoms ranged from 1 to 3 hours (median: 2 hours) from the time of ingestion of the barracuda. All cases experienced gastrointestinal (nausea, vomiting, diarrhoea) and neurologic (temperature allodynia, itchiness) symptoms but no cardiovascular manifestations. Urine and serum specimens of all eight cases showed CTX below the detection limit.@*Discussion@#The Philippines Epidemiology Bureau recommended that the Philippine Maritime Authority include CTX poisoning and its health risks in seafarers’ training to prevent future cases of CFP. The Event-based Surveillance and Response system will continue to provide a mechanism for the reporting and appropriate management of CFP cases.
RESUMEN
En el presente estudio se evaluaron algunos de los cambios microbiológicos y bioquímicos producidos en una especie de pez de consumo frecuente en Costa Rica, como lo es la barracuda Sphyraena ensis. Se evaluaron muestras de barracuda obtenidas durante la estación lluviosa y durante la estación seca. A cada una de éstas se le realizó un recuento aerobio psicrófilo, recuento e identificación de Vibrio, Enterococcus y Pseudomonas durante 6 días de almacenaje a dos temperaturas, 2 y 7ºC. Así también, se le realizó a cada una, la evaluación de la concentración de histamina producida mediante un inmunoensayo enzimático comercial. Los resultados obtenidos ponen de manifiesto que se da un incremento en los recuentos obtenidos a través del tiempo de almacenaje, dicho crecimiento es mayor al aumentar la temperatura de refrigeración. La mayoría de muestras mantenidas a 7ºC presentan recuentos superiores a 106 UFC/g luego de tres días de almacenaje, situación que no se presenta en las muestras mantenidas a 2ºC. No obstante, luego de 6 días de almacenaje, todas las muestras, independientemente de la temperatura de almacenaje, sobrepasan este valor. De la misma manera, se da un incremento en la concentración de histamina producida a través del tiempo de almacenaje, especialmente al conservar el producto a mayor temperatura debido al aumento de bacterias capaces de descarboxilar la histidina. No existe una diferencia estadísticamente significativa entre los recuentos obtenidos en estación lluviosa con respecto a la estación seca, no obstante, sí existe una diferencia con respecto a los géneros bacterianos aislados.
At the present study some of the microbiological and biochemical changes that occur through storage period in Sphyraena ensis, a fish specie of frequent consumption in Costa Rica were studied. Samples of S. ensis obtained during rainy and dry season were evaluated. Analysis included aerobic psychrotrophic count, identification and count of Vibrio, Enterococcus and Pseudomonas through a six day storage period at two different refrigeration temperatures, 2 and 7ºC. Same time, a commercial enzymatic immunoassay was used for the evaluation of the variation on the concentration of histamine produced in the different samples. Results obtained show that there is an increase on the bacteriological counts through the storage period, this increase is bigger as refrigeration temperature increases. Most of the samples maintained at 7ºC showed counts above 106 CFU/g after three days of storage, those stored at 2ºC did not present such high population levels. Nevertheless, after 6 days of storage, all samples, despite the storage temperature used, presented levels above the described one. Also, an histamine concentration increased through storage time, especially when the product was conserved at the higher temperature due to an increase in the number of histidine descarboxilating bacteria. There is no statistical difference between the counts obtained during rainy or dry season; nevertheless, there is a difference assicieated to the bacterial genera isolated.