SYDNEY, Feb. 21 (Xinhua) -- A Control Area set up by Biosecurity authorities in the Australian State of Tasmania has been expanded on Wednesday, as a fruit fly outbreak threatens the famed Tamar wine region.

Although Tasmania was believed to be free of the pest at present, throughout the rest of the country, the devastating tiny insect is estimated by Australia's Plant and Biosecurity Cooperative Research Centre to cost the Australian agriculture sector around 240 million U.S. dollars per year in market losses and control costs.

"Following the detection of a single adult fly last week in the statewide surveillance trap monitoring program, the Department immediately implemented an intensive surveillance program, including inspection of fallen fruit and the placement of additional traps around the detection site," Biosecurity Tasmania said.

"This monitoring has identified four additional fruit flies and larvae which indicates there is an active population in the vicinity of this site."

"Because of the detection, the Control Area in the north of the State is now required to be increased from the current area to include the northern coastal area to Beechford and Lefroy, Rowella, Sidmouth and to Kimberley in the South."

In order to contain the outbreak, the strict measures within the Control Area mean that no fruit can be transported more than 15 kilometres, essentially putting a halt on any exports.

"The Department is liaising directly with growers in the new Control Area to keep them informed of the latest information and identify measures to minimise impacts on them," Biosecurity Tasmania said.

At the moment around 50 wineries have been affected by the control zone.

But there is also grave concern for other fruit growers in the northwestern region as the pests can also be carried in apple, apricot, blackberry, capsicum, cherry, fig, lemon, loganberry, mulberry, nashi, nectarine, passion fruit, peach, pear, plum, quince, raspberry, strawberry and tomato.