The executive director of the Australian Chicken Foundation, Andreas Dubs, said the ducks were being destroyed after testing positive to a low pathogenic strain of the virus.

The outbreak does not pose the same health concerns as the potentially deadly H5N1 strain, which was first detected in 1997 in Hong Kong and has since devastated duck and chicken flocks in Cambodia, China, Egypt, India, Indonesia and Iran, according to the Department of Agriculture, Fisheries and Forestry.

There are no food safety issues, a statement on the department's Website said.

"The risk to human health is negligible," it said. "On occasions, low pathogenic avian influenza is detected in wild birds in Australia. This is not an unusual occurrence."

At this stage, the outbreak was restricted to two farms near the eastern city of Melbourne in Victoria state, according to Dubs.

Japan's farm ministry announced a ban on poultry imports from Australia on January 27, saying it wanted to prevent the spread of the virus.

Dubs said the ban by Japan, along with partial bans of poultry from Victoria by Hong Kong, Indonesia, Singapore and Vietnam, were "over reactions" given the limited outbreaks of the virus.

"This is limited to two farms, one of which has already been depopulated of ducks and the other is in the process," Dubs said.

In 2010, Japan imported 1.2 tons of poultry and 0.7 tons of eggs from Australia, according to Japanese trade data.

Australia exports about 4 percent of its poultry products each year to about 60 countries, with Hong Kong typically the biggest buyer, Dubs said.

Overall exports, which include eggs, chicken feed and other products are worth about A$40 million ($38 million) a year, he said.

Lab analysis has confirmed that 578 people have been infected with the H5N1 bird flu virus since 2003. Of those, 340 have died - a death rate never before seen from a flu virus.

The H5N1 birdflu killed six people in Asia in January 2012 - two in China, two in Indonesia and one each in Vietnam and Cambodia - up from zero in the same month in 2011.

The World Health Organization said these six people contracted the virus either directly or indirectly from birds, but the virus has not shown any dangerous changes or mutations.

"As far as we can see, the behavior of the virus has not changed. But these continued cases highlight the need for us to continue close surveillance of H5N1, watching for changes in the virus both in the laboratory and on the ground," the WHO said in reply to questions from Reuters.

(Reporting by James Regan; Additional reporting by Rie Ishiguro in Tokyo and Tan Ee Lyn in Singapore; Editing by Ed Davies)

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