The federal government banned raw prawn imports in January but lifted the ban in July in a move that devastated local prawn farmers who warned the imports could be dangerous.
Queensland's own prawn industry was crippled a year ago when white spot was detected in the Logan River south of Brisbane.
It crippled Queensland's multi-million dollar prawn industry and although it has not been proven, imported uncooked prawns are a suspected cause of the outbreak.
The three overseas shipments were detected the white spot by biosecurity tests despite an enhanced regime that requires exporting countries to certify their shipments are free of the disease.
The positive tests are certain to alarm the prawn industry which lobbied to prevent the lifting of the import ban.
One of the Logan River farmers who was the first to detect white spot had to destroy $1 million worth of his stock before Christmas last year.
Other farmers have questioned whether the certification from overseas prawn producers was adequate.
The Queensland Seafood Industry Association told a Senate Committee farmers had "absolutely no confidence in the new testing programs".
The Australian Prawn Farmers Association also railed against lifting the ban. White spot poses no risk to human health but is deadly to prawns.
Business News Australia
Get our daily business news
Sign up to our free email news updates.