School holidays, daylight savings and the onset of spring heralds a natural return to our beautiful Auckland beaches. However, The Auckland Regional Public Health Service (ARPHS) is still advising some caution at the beach - particularly on Narrow Neck and Cheltenham beaches. During August and September, 15 dogs become unwell with symptoms consistent with tetrodotoxin (TTX) poisoning after eating sea slugs at Auckland beaches. Five of these dogs died.

With no known further cases of TTX-poisoned dogs for the last two weeks, and no sea slugs detected in the last ten days, ARPHS is refining its health advice:

Children and pets still need to be supervised on Cheltenham and Narrow Neck beaches, and parents and owners should be cautious on other Hauraki Gulf beaches. Adults, children and pets should not eat anything found washed up on any Hauraki Gulf beach. Parents need to be aware of where their children are swimming or playing and what they are handling. Sea slugs on any beach must be avoided.

"With daylight saving starting this weekend, more people will be out and about taking advantage of the longer evenings and warmer weather on some of our beautiful Auckland beaches. It's second nature to most people to ensure children and animals are carefully watched when swimming and playing to avoid hazards and accidents. However, we're wanting people to be a little more cautious about what they handle on the beach, particularly at Narrow Neck and Cheltenham" says Dr Simon Baker - ARPHS Medical Officer of Health.

Following the death of a dog at Narrowneck Beach, sea slugs, both dead and alive, were found at both Narrowneck and Cheltenham beaches. Both the sea slugs and the vomit from the dead dog were tested and found to contain Tetrodotoxin (TTX). TTX is known to be a potent poison found in tropical puffer fish but not previously described in sea slugs. TTX is extremely toxic to humans and even a very small dose would be fatal.

"There is still some uncertainty over the origin of the TTX in the sea slugs. We don't know whether sea slugs can clear TTX from their systems, or if this is a one off or a recurrent, localised or generalised event. This means that anyone going to the beach must continue to be cautious," says Dr Baker.

Sea slugs are a ubiquitous organism, with a very wide range, in the marine environment of New Zealand. Strandings of sea slugs may occur anywhere, possibly related to prevailing weather patterns.

Early symptoms of TTX poisoning include numbness and tingling around the mouth, and nausea. This numbness and tingling can then spread to the face, tongue and other areas, with paralysis, in co-ordination and slurred speech. Medical attention should be sought immediately should any person become unwell after going to the beach - particularly after contact with a sea slug.

Dr Baker thanked the public for their cooperation with previous warnings and for the patience they have shown during the course of this event.

ARPHS will continue to update its public health advice as new information becomes available.

Information for a First Aid Response for Tetrodotoxin (TTX) Poisoning is available on the ARPHS website.