A paralytic toxin which has plagued Coromandel and Bay of Plenty shellfish since December last year is back.
On August 2 a health warning was finally lifted for the coastline from Tairua, east along the Bay of Plenty coastline, including Tauranga Harbour, Maketu and Waihi estuaries, to Whakatane Heads, but the health warning has today been reinstated.
Bay of Plenty medical officer of health Jim Miller said as a result of continual testing, high levels of paralytic shellfish poison has been detected along the coast.
"We strongly urge people to avoid all shellfish from this area until further notice. It is unfortunate that this warning has had to be reinstated so soon, however this is a natural occurrence which is difficult to predict," Dr Miller said.
The health warning affects all bi-valve shellfish, including mussels, pipi, tuatua, cockles, oysters, scallops, catseyes and kina.
Paua, crayfish and crabs could still be eaten, but the gut should be removed before cooking.
The paralytic shellfish toxin could cause numbness and tingling around the mouth, face or extremities, difficulty swallowing or breathing, dizziness, double vision, and in severe cases, paralysis and respiratory failure.
The symptoms usually occurred within 12 hours of eating the affected shellfish, Dr Miller said.
Monitoring of the shellfish will continue.