A grape disease that hasn't been found in Australia has been identified in three separate states.
Red blotch has been detected in wine grape collections in Victoria, Western Australia and South Australia.
While collections are used for propagation, the virus has not been discovered in commercial nurseries or vineyards.
According to Australian Grape and Wine Chief Executive Tony Battaglene, it was picked up during random biosecurity testing.
It looks like it's coming in when people have brought in grape vines from probably the United States, he said.
The virus prevents photosynthesis in grape vines, affecting the fruit.
The sugars don't go into the grape itself, they stay in the leaf, according to Mr Battaglene.
Some of the bunches don't ripen until later, and some of the berries don't ripen.
They've got reduced sugar content, they've got poor colour, and there are impacts on the tannins and phenolics, all of those things that give you the flavour profile.
The industry is working with the state governments in WA, SA and Victoria to find out exactly where the virus is in Australia.
When there is a suspected incursion or an identified incursion, a system is set up with the state authorities and industry.
We have a technical group which is trying to identify whether it is possible to eradicate this and the potential spread, Mr Battaglene said.
Then it will go to a decision-making process of what action we need to take. The detection in Australia is recent but it's believed that the virus has been around for a long time.
It looks like there was some infected material brought in a long time ago, probably 10 or 15 years ago, Mr Battaglene said.
The virus was first discovered in California's Napa Valley in 2008, but is believed to have been around for a long time because it is similar to another grapevine virus that escaped attention.
It's believed there is no Australian equivalent currently, which could be preventing transmission.
There's no reason for panic and eradication is essential, according to Battaglene.
He said that the virus has the potential to seriously affect the quality of grapes.
With climate change, you never know what other factors could come to the country, which could cause it to become a problem.