White spot virus as 'uncontainable as COVID' as department detects disease in wild prawns

White Spot is condemning the Clarence River prawn fishers to life in limbo due to the biosecurity shutdown of the industry. (Supplied: DigsFish Services)

A potentially destructive disease detected in prawns off the NSW North Coast has been described by an aquatic veterinarian as being “uncontainable”.

White spot disease has been detected in wild prawns in the inshore ocean near Evans Head in northern NSW.

Known as white spot syndrome virus, the disease does not affect humans, but it is deadly for prawns and other crustaceans, including crabs.

It was found in New South Wales for the first time in prawn farms in the Clarence Valley in 2022.

However, this is the first detection of white spot in wild school prawns.

Biosecurity control order in place

NSW chief veterinarian Joanne Coombe said testing was already underway to determine if the latest detection was linked with previous cases.

“I certainly wouldn’t want to say, ‘No, there is nothing we can do’, not until we can establish exactly what type of virus we have,” Dr Coombe said.

A biosecurity control order has been imposed, which restricts the movement of uncooked prawns as well as raw decapod crustaceans, including crabs, lobsters and crayfish, from the Evans Head area for the next three months.

The current control orders will be in place until comprehensive testing can be completed on the infected prawns.

“I will meet with all the other chief veterinary officers and the Australian chief veterinary officer to determine next steps,” Dr Coombe said.

“That will be dependent on whether it’s the same strain … or if it’s an entirely new strain.”

First outbreak closed three prawn farms

White spot is believed to have made its way into Australian waters through recreational fishers using imported raw prawns as bait.

The first outbreak of the exotic disease in 2016 decimated prawn farms on the Logan River in south-east Queensland.

The 2022 detection resulted in the closure of three major prawn farms on Palmers Island.

Aquatic vet Matt Landos said the detection of the virus in wild prawns was a sign it was now endemic.

“The case is that the horse has bolted,” he said.

While Dr Landos said the disease could be destructive in prawn farms, there was not enough data to indicate the impact on wild fisheries.

“It’s as uncontainable as COVID. We can’t control where the crustacean move across our coast,” he said.

“We cannot disinfect the ocean.”

Bad news for fishing industry

For the industry, the effects of the latest detection are unclear.

Ballina prawn trawler operator John Joblin said the impacts could be felt across the broader industry.

“It’s going to affect everyone with anything to do with crustaceans. It’s not good news at all,” he said.

Mr Joblin said the restriction on uncooked prawns grown domestically, which were commonly used for bait, could impact businesses.

“Now that green [uncooked] market is gone, it’s not a very good thing for those fisheries if it gets into the Clarence River.”