A public health warning has been issued against collecting or eating shellfish harvested in parts of Waikato.
It includes areas from Mohakatino to Manukau Harbour, Kawhia, Aotea and Raglan Harbours.
Routines tests on samples have shown levels of Paralytic Shellfish Poisoning above the safe limit.
The levels in Manukau Harbour are safe though.
Symptoms of illness include numbness and tingling around the mouth, face or extremities, difficulties in swallowing or breathing, dizziness, double vision, and in severe cases, paralysis and respiratory failure.
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