Ciguatera: Food poisoning in tropical areas
caused by eating fish that lives in coral reefs. These fishes eat different toxins, one of which is called ciguatoxin, when feeding on algae adhered to corals.
This disease is endemic in the tropics and subtropics between 35 degrees north and south latitude, embracing all Caribbean islands. It is believed the term comes from the aboriginal word cigua so as to designate an endemic snail at the coast of Cuba in the eighteenth century. The first time an explicit reference was made to ciguatera was in 1774, in New Caledonia, when the crew of the English Captain James Cook felt sick.
What are the symptoms of this food poisoning? Some symptoms are common to other conditions and usually occur after eating and even 12-24 hours later. They are gastrointestinal effects (diarrhea, nausea, vomiting, abdominal pain); neurological (cramps, tingling sensation, metallic taste in the mouth, loss of teeth sensation, muscle aches); and cardiovascular (bradycardia or tachycardia, hypotension, shock). In addition, there are two characteristic symptoms of ciguatera. One is the reversal of thermal sensation, that is, to feel hot when touching cold objects and vice versa. The other symptom is tingling around the mouth (lips and tongue).
The duration and severity of symptoms vary according to the amount and serving of fish eaten. In addition, one peculiarity of ciguatera is its worsening; it means that symptoms can reappear over time after eating seafood, alcohol or walnuts.
The population with fewer resources that lives on fishes is the most affected by ciguatera. The second place is for tourists who visit tropical areas. But this disease is not exclusive to such zones because the tourism has increased and the marketing of fish belonging to tropical areas have caused ciguatera comes out in other latitudes and thus its impact is higher. It has been reported about 50,000 cases a year and a mortality rate that varies between 0.1 and 1%. The cause of death is usually due to respiratory failure.
Treatment consists in the use of antihistamines, analgesics or anti-inflammatory, among others, but the most effective for this food poisoning is the use of mannitol, which reverses the symptoms. Before medication we have to make sure to rehydrate the patient, because vomiting and diarrhea could lead to dehydration.
As we don't know for sure when a fish is contaminated we can take into account several factors such as the species of fish, fishing area, fish size, the amount and parts of the fish to be consumed or season of the year in which it is caught. It is said that the higher the water temperature the higher the risk of contamination.
We must to keep in mind that ciguatoxin is thermostable, which means that it remains stable to heat, cooking and freezing and it doesn't matter how cooked the fish is, the guest who eats it will be infected. It is colorless, odorless and tasteless.
The Dominican Republic is one of the areas where ciguatera is a common disease. Puerto Plata, La Romana, Pedernales, Palenque and Montecristi are considered risk areas. Fortunately, the coast of Barahona is free of it. Being aware of this fact and in order to prevent it, the Ministry of Environment and Natural Resources and the International Atomic Energy Agency (IAEA) organized last November a specialized training aiming to supervision on the ground and data management on toxins in cases of ciguatera for eleven countries of Latin America and the Caribbean.