Infected prawns are still making it onto supermarket shelves despite tougher rules meant to protect farmers from another devastating outbreak of White Spot disease.
Prawns bought from 10 retail outlets were tested for the virus by University of the Sunshine Coast professor Wayne Knibb who found about one third had been or were infected.
"Clearly, if we can find in a very limited sample 30 per cent of samples that were in the history connected or in contact with the virus, then clearly we're playing with fire here," Professor Knibb told the ABC's Four Corners program.
"We have a route of a virus that is a particularly dangerous virus and shown worldwide just how destructive it can be. It's damaged whole national economies, and it's cost billions of dollars."
White spot poses no risk to human health but is deadly to prawns.
A white spot outbreak in 2016 is estimated to have cost prawn farmers and associated industries almost $400 million.
Biosecurity checks on seafood imports lie with the Federal Government.
Agriculture Minister David Littleproud's office has questioned Professor Knibbs' testing and accreditation.
But ABC reports test results were verified by an independent lab.
Mr Littleproud's department says protocols for imported green prawns are strict, but says they are only meant to reduce the biosecurity risk to a low level, but not zero.
"There is insufficient evidence to support an argument that these enhanced import conditions for prawns are not working," a Department of Agriculture spokesman said.
"It is also vital to remember that the department has been very clear that its enhanced import conditions do not guarantee that there will never be (white spot) present in prawns imported into Australia."
White spot was detected in the Logan River south of Brisbane and at three of eight land-based prawn farms in 2016, crippling Queensland's multi-million dollar prawn industry.
Imported uncooked prawns were a suspected cause of the outbreak, although it was never proven.
The disease was later found in wild prawn stocks in Moreton Bay.
Tests carried out on three shipments of raw prawns in November showed a positive result, after an import ban was lifted.
Australian Associated Press
