CHP investigates suspected case of paralytic shellfish poisoning

     The Centre for Health Protection (CHP) of the Department of Health is today (October 27) investigating a suspected case of paralytic shellfish poisoning affecting a family of three.

     The case involves one male and two females aged 35 to 58, who presented with blurring of vision and perioral and tongue numbness from 10 to 25 minutes after consuming jade spiral shells at home on October 24. All attended the Accident and Emergency Department of North District Hospital on the same day and one required hospitalisation. All patients have been in a stable condition all along.

     Initial enquiries revealed that the jade spiral shells were purchased from a seafood stall in Shek Wu Hui Market in Sheung Shui. Investigations by the CHP and the Food and Environmental Hygiene Department are continuing.

     "Paralytic shellfish poisoning toxin is a natural toxin sometimes found in bivalve shellfish. It is heat-stable and cannot be destroyed through cooking," a spokesman for the CHP said.

     "The symptoms of paralytic shellfish poisoning are predominantly neurological and the onset is usually within minutes to hours after ingestion of the shellfish. Initial symptoms may include tingling, numbness of the mouth and extremities, headache, dizziness and gastrointestinal discomfort. In the majority of cases, symptoms resolve completely within a few days. In severe cases, difficulty in swallowing and speech, paralysis with respiratory arrest and even death may occur," the spokesman added.

     The spokesman reminded members of the public that they should seek medical advice immediately if they develop shellfish poisoning symptoms and save any leftovers for investigation and laboratory testing.

     To reduce the risk of shellfish poisoning, the public should:

* Buy shellfish from reliable and licensed seafood shops;
* Remove the viscera, gonads and roe before cooking and discard any cooking liquid before consumption;
* Eat a smaller amount of shellfish in any one meal; and
* When symptoms occur after consuming shellfish, seek medical advice immediately.