CHP investigates suspected ciguatoxin poisoning case

     The Centre for Health Protection (CHP) of the Department of Health is today (September 11) investigating a suspected ciguatoxin poisoning case affecting two persons.

     The case involves a 33-year-old female and a 44-year-old female who developed symptoms of ciguatoxin poisoning including abdominal pain, diarrhoea, dizziness, limb numbness and nausea about two and 10 hours respectively after consuming fish for dinner at home on September 9. The patients attended the Accident and Emergency Department of Pok Oi Hospital yesterday (September 10) and were admitted for treatment. They have been discharged and are in stable condition.

     Initial enquiries revealed that the fish consumed was brought from Okinawa by a friend of the patients on September 9.

     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 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 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.