In the wake of Hurricane Richard (which we rode out safely on board), we saw a lot of problems from the rain and flooding like gastrointestinal disease and fevers, but we also saw cases of Ciguatera toxin poisoning.
Ciguetara poisoning is caused by eating large predatory reef fish that have accumulated high amounts of cigautera toxin. Odorless and tasteless, the toxin causes Gastrointesinal and Neurological symptoms:
- Nausea, vomiting, diarrhea
- Headache, muscle aches, tingling, loss of balance, hallucinations
- Cold allodynia (burning sensation on cold contact)
- Poor circulation and shooting pains in the chest due to vasospasm
It appears that the toxin can even be sexually transmitted, and babies breastfeeding from poisoned moms develop facial rashes and diarrhea so it probably is transmitted in breast milk as well.
Ciguatera’s bizarre repertoire of symptoms, especially because the symptoms can last intermittently for up to 20 years (although most people recover within a few weeks), sometimes leads to a diagnosis of multiple sclerosis by physicians unfamiliar with this condition. A history of travel in the tropics, or the consumption of imported tropical reef fish in restaurants outside the belt of ciguatera distribution, is therefore an important part of the clinical history for patients with atypical MS symptoms or long-term GI issues.
Found in all tropical waters, ciguatera toxin is produced by dinoflagellate plankton (tiny photosynthesizing organisms) that bloom in huge numbers near river mouths, or after heavy rains and seas that wash lots of sewage and topsoil into the water and stir everything up. All these nutrients cause blooms of the dinoflagellates, and in the weeks after big storms it is especially dangerous to eat grouper, snapper, and other large predatory reef fish that quickly acculumate dangerous levels.
There is no known treatment for ciguatera, except for supportive care. Most care is focused on treatment of symptoms (pain, fever, etc), and by trying to flush the toxins with various herbal remedies or IV mannitol (differing opinions on the efficacy of mannitol). There is also no practical checmical assay to test fish either.
Avoiding ciguatera means not eating large reef fish, BUT there are some local methods used both in Haiti and here in Honduras for trying to detect ciguatera. The most common we have seen is that pieces of the fish are placed on an anthill, and if the ants reject it, so should you! Also, it is widely believed that cats will show symptoms after ingesting poisoned fish, and that flies will not land on contaminated fish.
Other traditional remedies include bedrest after a guanabana enema, bleeding and porting directly from the GI tract, cleansing with a dove (Santeria ritual), and tea made from mangrove buttons (high in vitamin B, which may help induce diuresis and more rapid excretion of the toxins).
A busy week at our clinic in Oakridge…ciguatera on top of everything else! And now another hurricane is on its way–this one might be a big one if it hits here..could be a lot more ciguatera cases on the way if this keeps up. So far, in Oakridge alone, where the primary protein intake is fish and Ciguatera is a higher risk, we have distributed over 12,000 vitamins. If vitamin-induced diuresis helps, hopefully this will reduce the symptoms of some of the sufferers there.