Ciguatera fish poisoning is a foodborne illness caused by consuming fish that have accumulated toxins from marine algae, particularly the dinoflagellate Gambierdiscus toxicus. These toxins can affect various fish species, especially those found in tropical and subtropical waters, such as barracuda, grouper, and snapper. Symptoms of ciguatera poisoning can include nausea, vomiting, diarrhea, and neurological effects like tingling or numbness. The illness can last for days or even weeks, and there is no specific antidote. Prevention involves avoiding certain reef fish in areas known for ciguatera outbreaks.