The warning comes after Department of Primary Industries personnel found Queensland Fruit Fly in fruit growing around the Swan Hill area.

Personnel are also monitoring reported sightings around Barham and Koondrook.

“When an outbreak is declared, which has not happened at Swan Hill, it will mean that growers within a 15 kilometre radius will need to treat their fruit before it is sent off to markets,” Queensland Fruit Fly state operations manager, Bill Ashcroft said.

Fruit flies can lay eggs in all types of maturing or ripe fruit, such as stone fruit, citrus, loquats and quinces, as well as some vegetables, including tomatoes, capsicums, and chillies.

Tiny creamy-white maggots hatch from the eggs and burrow through the fruit as they feed.

Infested fruit can look perfectly good on the outside but is mushy and brown on the inside.

To prevent a potential outbreak, residents are being asked not to transport fruit grown in backyards throughout the area.

It is safe to travel around the district with fruit purchased from supermarkets and greengrocers.

“We ask people not to travel with fruit, especially if they have come from the north or the east – areas where fruit fly have been detected,” Mr Ashcroft said.