An unlikely coalition of farmers, environmentalists, scientists and fishers has called for the Government to do more to protect Australia's largest river system from a plague of introduced fish.

European carp have infested the waters of the Murray-Darling Basin in their millions.

Key points: European carp account for 90 per cent of fish in river system

European carp account for 90 per cent of fish in river system CSIRO investigating possibility a herpes virus can control the species

CSIRO investigating possibility a herpes virus can control the species Alliance of groups including farmers, environmentalists want virus released

They churn up mud, making the water uninhabitable for native fish, insects and birds.

In some areas they have become so dominant, they now make up 90 per cent of all fish in the river.

For the past seven years, CSIRO scientists have been investigating the potential efficacy of an Indonesian strain of carp herpes as a way to control the fish.

The virus could kill carp only, leaving other fish and animals unscathed.

"We're getting toward the end of the scientific end of the work," lead researcher Ken McColl said.

"The main thrust of our work at CSIRO has been to look for any untoward effects of this virus on other species.

"We don't want the virus to affect anything other than carp.

"Over quite a number of years we've looked at about 13 species of native fish ... and we've not been able to find any evidence of disease or virus multiplication in any of those species.

"So we don't believe it does anything in any other species."

Dr McColl said the scientists have also investigated the affect of the virus on yabbies, mice and chickens and have also researched cases where humans have come into contact with the disease.

"We're fairly confident that it's not going to cause problems elsewhere," Dr McColl said.

Farmers, environmentalists back release of carp virus

Usually at opposite ends of Murray-Darling issues, the Australian Conservation Foundation and the National Irrigators Council have joined calls from the National Farmers Federation, the Australian Recreational Fishing Foundation, the Invasive Species Council and the Invasive Animals Cooperative Research Centre for the virus to be approved for release.

"People often focus on the difference in opinions between environmentalists and farmers, but we actually have a lot in common and healthy rivers is absolutely one of those matters," said Jonathan La Nauze, acting campaigns director for the Australian Conservation Foundation.

"Getting on top of carp is essential if we want healthy rivers and that's why farmers, fishermen and environmentalists are all standing united behind this proposal.

A pile of carp taken from a cage trap set in the Murray-Darling Basin. ( Supplied: Invasive Animals Cooperative Research Centre )

"It really would complement the work of the Murray-Darling Basin Plan, the hard work that we've been going through in restoring environmental flows.

"It's time our Government stepped up to the plate and funded this terrific work in releasing a biological control into the Murray-Darling Basin."

Matthew Barwick from the NSW Department of Primary Industries has added his voice to the chorus.

He said the approvals would take "a couple of years" to process, with hurdles in four separate pieces of Commonwealth legislation.

"It would be one of the largest control initiatives in Australia," Mr Barwick said.

Australia has a history of using viruses to control introduced animals.

The myxoma and calici viruses were effective in knocking down rabbit numbers.

And a feline parvovirus was used effectively to control feral cats on Marion Island.