Nine reports of suspected ciguatoxin food poisoning cases have been confirmed, involving 33 people aged 16 to 88. Twelve have been hospitalised and are stable.

The Centre for Health Protection said the 13 men and 20 women developed symptoms like limb numbness, diarrhoea, abdominal pain and vomiting 30 minutes to 13 hours after eating tiger grouper bought from a Kowloon City market on May 11. Thirty-one sought treatment in hospitals.

To prevent ciguatera fish poisoning:

* eat less coral reef fish, especially fish weighing over three catties;

* eat only a small amount of coral reef fish at any one meal;

* avoid eating the head, skin, viscera and roe which usually has a higher concentration of toxin; and,

* avoid consuming alcohol, peanuts or beans when eating such fish.