Fish caught offshores in the deep oceans rarely get poisonous, and most resorts buy their fish from offshore trawlers, as do the supermarkets. Very briefly it is a serious illness caused by eating coral reef fish that have accumulated a high level of antural toxins through their diet. Over 500 different types of fish can get poisonous from ingesting certain dinoflagelates on the reefs, such as amberjack, barracuda, grouper, mackerel, moray eels, mullet, parrot fish, red snapper, sea bass and surgeon fish. The most risky are larger carnivorous fish that live near coral reefs. To reduce the risk, prefer the smaller, younger fish, and don't eat the heads or internal organs, which retain more toxins.
Cases can range from very mild to serious.
If you get any of these symptoms after eating fish it is advisable to contact a doctor immediately. There is no certain antidote, but Mannitol is often injected as a first step. In its acute form, dengue is characterized by flu-like symptoms including severe pain in the head, eyes, muscles and joints. The incidence of both forms of dengue infection has recently been increasing, as expanding urbanization enlarges the regions inhabited by the Aedes mosquito vector. Mosquitoes capable of transmitting this disease are also found within the United States.