Ciguatera poisoning is a food borne illness caused by eating the contaminated flesh of certain sport fish, primarily barracuda, grouper, amberjack, hogfish, snapper, mackerel and mahi mahi taken in the Bahamas and off the Florida Keys.
Consuming the food borne toxin can result in severe nausea, vomiting and diarrhea, headache, muscle aches, joint pains, and a long-term tingling in the limbs. The neurological symptoms caused by the toxin can sometimes cause medical personnel to give a misdiagnosis of multiple sclerosis.
Most experts say the chance of contracting Ciguatera poisoning is rare, but after a review of available data as well as further study into the food borne illness statewide, make it clear that estimates will have to be revised upwards. “The rate of illness was found to be higher than previously estimated. Areas around Miami and in the Florida Keys are particularly affected,” according to study author Elizabeth Radke, Ph.D.
Dr. Radke recommends that people should stop eating the affected fish, but they need to be aware of the risks. The study found that Hispanics had the highest rate of Ciguatera poisonings, but this is due more to cultural traditions that favor eating barracuda.
Study by the University of Florida’s Emerging Pathogens Institute, and Florida Department of Health
According to Florida Health Department records, previous estimates put the incidence of Ciguatera poisoning at 2 cases per 100,000 people. The new estimates based on the study show an incidence rate of around 5.6 cases per 100,000 persons.
“I think there is a broader awareness the farther south you go that barracuda are carriers but perhaps not as much awareness that a fish like grouper or amberjack can carry ciguatera,” said Radke.
According to Radke, there are two reasons the disease has been so under-reported. Physicians are not reporting cases to the health department, and many people may be thinking the illness is something else, and don’t seek medical care. But Ciguatera poisoning has been given top priority now.
The Ciguatera toxin and how it spreads
Ciguatera toxin poisoning is caused by eating certain reef fish whose flesh is contaminated with the toxins originally produced by dinoflagellates that live in tropical and sub-tropical waters. The dino flagellates adhere to coral, seaweed and algae, where they are in turn, eaten by herbivorous fish. Ciguatera poisoning is the most common form of fish-related food poisoning.
These small herbivorous fish are then eaten by carnivorous fish, effectively moving up the food chain. Gambierdiscus toxicus is the primary dinoflagellate responsible for the production of a number of toxins causing Ciguatera. These include ciguatoxin, maitotoxin, scaritoxin and palytoxin. And it is the predator fish, many of them sport fish that cause the food borne illness humans get.
Ciguatera is colorless, odorless, tasteless, and not affected by freezing or cooking. Dr. Radke also voices concerns about Ciguatera moving northward as the ocean’s temperatures continue to warm. This means that the Ciguatera toxin could spread even further.
The study by Dr. Elizabeth Radke and her associates was published on June 29, 2015, in the American Journal of Tropical Medicine and Hygiene under the title: Epidemiology of Ciguatera in Florida.
