Press Release

CHP investigates suspected ciguatoxin poisoning case

25 September 2014

The Centre for Health Protection (CHP) of the Department of Health is investigating a suspected ciguatoxin poisoning case affecting a 38-year-old man.

The patient, with good past health, developed symptoms of ciguatoxin poisoning including facial and tongue numbness, skin itchiness over the forehead and the neck, abdominal pain and diarrhoea about two to three hours after eating a marine fish at home on September 24.

He attended the Accident and Emergency Department of Pamela Youde Nethersole Eastern Hospital on September 25 and was subsequently admitted. He is now in stable condition.

The CHP's investigations are ongoing.

A CHP spokesman said ciguatera fish poisoning is not uncommon in tropical areas. It is mainly associated with the consumption of big coral reef fish that have accumulated the toxin in the body, in particular in internal organs, through eating small fish that consumed toxic algae in coral reef seas.

A larger fish is therefore more likely to carry higher amounts of the toxin. However, it is not easy to tell from the appearance of the fish whether it contains the toxin.

People affected may show symptoms of numbness of the mouth and the limbs, vomiting, diarrhoea, alternating sensations of coldness and hotness and pain in the joints and muscles.

The spokesman said that most people affected by ciguatoxin would recover without long-term health effects.

However, if excessive toxins are consumed, the circulatory and nervous systems can be affected.

"The toxin cannot be destroyed by cooking," the spokesman said.

To prevent ciguatera fish poisoning, members of the public should observe the following measures:

• Eat less coral reef fish;
• Eat small amounts of coral reef fish at any one meal and avoid having a whole fish feast in which all the dishes come from the same big coral reef fish;
• Avoid eating the head, skin, intestines and roe of coral reef fish, which usually have a higher concentration of toxins;
• When eating coral reef fish, avoid consuming alcohol, peanuts or beans as they may aggravate ciguatoxin poisoning;
• Seek medical treatment immediately should symptoms of ciguatoxin fish poisoning appear; and
• Coral reef fish should be purchased from reputable and licensed seafood shops. Do not buy the fish when the source is doubtful.