The importation of green prawns into Australia has been temporarily suspended following the discovery of white spot disease in Queensland prawn farms.
The disease, which is harmless to humans but kills prawns, has been found on five properties on the Logan River between Brisbane and the Gold Coast. White spot has also been detected in a crab on one farm.
Farms without the disease have been quarantined, but can still harvest prawns for sale.
Deputy prime minister Barnaby Joyce suspects the disease spread after imported green prawns used as bait infected waterways.
"I was told that they are detecting white spot in imported green prawns that you buy in the shop for human consumption," Joyce said on Friday. "That, for me, is a huge concern. It means they get into the waterways, it means it can infect prawn farms."
Joyce is urging all Aussies to keep consuming prawns this summer, but not to use imported green prawns as bait.
"If you are buying green prawns, or you have bought them from retail outlets, please do not put them in a waterway or use them as bait," he said. "If you cook a prawn, it kills the white spot in any case."
One prawn importer has already been told their licence will be revoked for not following proper protocols, and a number of others are being investigated.
Australian Prawn Farmers Association's Nick Moore told the ABC he supported the ban. He said the issue was one his organisation had been highlighting for "many years".
"While I absolutely applaud the government's stance on it right now, it would have been nice a couple of years ago," he said.
Joyce, who cut short a family holiday in Coolum to deal with the issue, said the chief scientist is taking charge of chlorinating the infected farms to kill the disease.
"Biosecurity is incredibly important to this nation," he said.
Around $50 million worth of greens prawns are imported into Australia annually.