CHP investigates suspected ciguatoxin poisoning case

     The Centre for Health Protection (CHP) of the Department of Health is today (July 20) investigating a suspected ciguatoxin poisoning case affecting two persons.

     The case involves a male and a female both aged 46, who developed symptoms of ciguatoxinpoisoning including abdominal pain and diarrhoea, as well as numbness over face, tongue and limb about six hours after consuming fish during dinner at a restaurant in Mong Kok on July 18. The duo sought medical attention at the Accident and Emergency Department of United Christian Hospital yesterday (July 19) and did not require hospitalisation. They are in stable condition.

         Initial enquiries revealed that the fish consumed was brought from Okinawa. Investigation by the CHP is ongoing.

         Ciguatera fish poisoning is not uncommon in tropical areas. It is mainly associated with the consumption of large coral reef fish which have accumulated the toxin in the body, particularly in internal organs, through eating small fish that consumed toxic algae in seas around coral reefs.

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

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

     "Most people affected by ciguatoxin will recover without long-term health effects, but if excessive toxins are consumed, the circulatory and nervous systems can be affected. The toxin cannot be destroyed by cooking," a spokesman for the CHP said.

     To prevent ciguatera fish poisoning, the public should:

• Eat less coral reef fish;
• Eat small amounts of coral reef fish at any meal and avoid having a whole fish feast in which all dishes come from the same large 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 in doubt.