Despite the Paralytic Shellfish ban being lowered in the Coromandel area, the ban still remains in place for the Bay of Plenty.

Medical Officer of Health, Dr Phil Shoemack, says there have been no reports of people collecting and eating shellfish since December.

People are being warned not to collect and consume shellfish in the Bay of Plenty.

He says there is no timeline of when the ban will be lifted.

'The toxins produced by algae in the water can occur during any time of the year, but it's more common in the summer months. 'The levels through the main part of the bay of plenty are still quite high and worryingly so, it's reassuring that we've had no further reports of people getting sick since the beginning of December.” Opito Bay and Whitianga have been removed from the banned areas list.

The affected areas include: the entire coastline from Tairua Harbour to Whakatane, Pauianui, Opoutere, Onemana, Whangamata, Waihi Beach and surrounding estuaries.

The warning applies to all bi-valve shellfish including mussels, pipi, tuatua, cockles, oysters, scallops, as well as catseyes, and kina (sea urchin). Shellfish in affected area shouldn't be taken or eaten.

Paua, crayfish, and crabs can still be taken but as always, the gut should be removed before cooking.

Consumption of shellfish affected by the paralytic shellfish toxin can cause a range of symptoms.

They include: numbness and tingling around the mouth, face or extremities; difficulty swallowing or breathing; dizziness; double vision; and in severe cases, paralysis and respiratory failure.

These symptoms usually occur within 12 hours of a person consuming affected shellfish and anyone suffering illness after eating shellfish should seek medical attention.

Monitoring of toxin levels will continue along the coast and any changes to the warning area will be communicated accordingly.