A THIRD of the Australian prawn farming industry could be wiped out after white spot disease was detected at a fifth property on the Logan River and authorities admitted they did not know how the contamination was spreading.
The latest outbreak occurred 4km downstream from the previous four contaminations, leading farmers to fear the disease was wild in the Logan River.
Just two prawn farms on the river, which houses Australia's largest cluster of farms and hatcheries, remain disease-free and $25 million has been wiped from the industry since white spot, which does not pose a risk to humans, was confirmed in early December.
Rocky Point Prawn Farm owner Murray Zipf said he feared the disease would soon carry downstream to his 12 ponds near the river mouth.
"I'm going to church on Sunday and that's about all I can do," Mr Zipf said.
"It's the end of prawn farming here, we'll have to bring in prawns from overseas now."
Biosecurity Queensland has enforced emergency restrictions on movement and fishing activities on the river, but still does not know where the disease came from or how it had moved between properties.
Chief biosecurity officer Jim Thompson said the agency began treating infected ponds with chlorine last week and heightened surveillance measures had been put in place.
Australian Prawn Farmers Association executive officer Helen Jenkins estimated that up to a third of the industry could be wiped out if hatcheries in the river could not be restarted.
She said the damage to the industry was directly affecting 115 families, not including flow-on industries.
Until the disease was detected in November, Australia had been considered free of white spot, which has decimated the prawn industry in Asia and the Americas.
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