Deadly Disease of Reef Fish Can Be Fought With 9 Lives

A sometimes fatal disease that comes from eating fish caught around coral reefs is on the rise in the South Pacific, according to the South Pacific Commission, which monitors the health of island people.

“Although it’s always been there, it’s now starting to be an economic problem,” said Dr. Richard Taylor, an epidemiologist with the commission, a regional organization of Pacific island nations, as well as the United States, Britain and France. It is affecting the area’s inshore fishing industry and could harm tourism, Taylor said.

There is no known cure for the disease, called ciguatera, which afflicts those who eat fish caught around South Pacific coral reefs.

Deep-sea fish are safe, as are bottom-feeding fish and crustaceans.

Island people have known of the affliction for centuries. One of the symptoms is a burning, itching sensation on the hands and face, Taylor said.

It usually hits the central nervous system within 24 hours. In its severest form, a victim will collapse, the hands and feet become numb and heart seizure can follow.

The ciguatera toxin is one of the most poisonous substances known and was identified only in the past 10 years, Taylor said.

It comes from an algae that grows on coral reefs damaged by storms or through man-made activity, such as blasting holes to create boat channels.

“The toxin is carried by a small unicellular organism, which feeds on the algae that grows on the dead coral,” said Taylor. “Small fish eat the algae, big fish eat them and bigger fish eat them.

“The concentration of the toxin gets bigger and bigger in the large fish, like barracuda and red snapper. Moray eels also have high concentrations.”

Taylor said there is no antidote for ciguatera and no simple way to determine whether a fish is carrying it.

“The only test really is the cat test,” Taylor said. “Feed some to your cat and if it keels over, don’t eat the fish.”