[First published on www.abc.net.au] RECREATIONAL fishers have renewed calls for a ban on the importation of uncooked prawns after the discovery of the devastating white spot disease in Queensland prawns.
Australia had been the only major prawn-growing country free of the highly contagious white spot virus, until it was found earlier this month on prawn farms between Brisbane and the Gold Coast. The disease causes white spots in prawns and can stop them from growing.
Outbreaks across Asia and the Americas have reduced prawn farm outputs to about 40 per cent of their normal production. The industry had previously warned that white spot could potentially be brought in with uncooked frozen prawns.
Authorities are now investigating whether that was what happened. The virus was detected on three farms along the Logan River, where prawns have been destroyed and ponds decontaminated. Another five unaffected farms were placed under heavy restrictions after the disease was found in wild prawn populations in the Logan River.
Dr Barry Pollock, a fisheries scientist who represents recreational fishers through the group Sunfish, said it looked like the disease was fairly widespread in southern Moreton Bay. “How it got there is basically unknown at this stage, although it would have to be associated with the importation of green uncooked prawns,” he said.
He said until recently white spot virus was unknown as a “natural disease” and because of that he was certain of its association with imported frozen prawns. Dr Pollock said there were a number of ways in which the virus could have been transferred from a frozen green prawn to Australian fisheries. “It’s just a matter of someone dumping some of those prawns or dumping the shells after they’ve peeled them for cooking, into the rivers,” he said. “Or another possibility is that they’ve been used for bait. Personally I’d like to see a ban on all uncooked seafood imported into Australia. There’s no problem with cooked product because that would kill any viruses and other pathogens that are likely to be there.”
Commercial fishers say they had flagged the disease risk from uncooked Asian prawn imports for years, with no response. Matt West, from the Australian Prawn Farmers Association, said they had been lobbying ‘pretty hard to try and change it’. “As far as we’re aware, green product coming in has to be tested,” he said. “But ultimately you can’t stop everything and that’s always a risk to us.”
Biosecurity Queensland chief executive Jim Thompson said he was sure the issue would be taken up again with the Commonwealth Government. He said the only other time white spot had appeared in Australia was an isolated case in the Northern Territory. That outbreak has been eradicated.
But Mr Thompson warned it was too early to say how the virus came to Queensland. “One of the most important things we do with all these incidents is try and work out where they started from,” he said. “Sometimes that’s impossible, but it’s always a critical part of any response. So we are doing a lot of tracing of material that we can find and movement of people, movement of products, movement of anything that may have actually brought the disease in.”
He said there was a lot more work to be done in the wild fishery to confirm where the virus was. Government representatives will meet on Tuesday with the industry near Moreton Bay to discuss the outbreak.