The 21 members of the Asia Pacific Economic Cooperation group - known as APEC - have ended a major bird flu disaster exercise in Australia, testing how well various countries would communicate during a pandemic.
Australian officials call the 26-hour drill "an important milestone" in emergency planning in the APEC region.
It was the first time an exercise of this scale has been held involving the major economies of the Asia-Pacific region, including China, Japan and the United States.
Participants were presented with a nightmare scenario.
They were faced with a hypothetical outbreak of the deadly H5N1 virus among fishermen in an unidentified Asian village, which then leads to human-to-human transmission.
It was a test of how countries could coordinate and cooperate in a serious outbreak.
Officials have warned that air travel means people could spread the disease to different countries within hours, making fast notification of an outbreak crucial.
The simulation was held in Canberra and organized by Australia and Singapore. It began Wednesday and ended Thursday. The results will be discussed at a summit in Singapore in August.
Alistair Wilson from Emergency Management Australia said Thursday it was a worthwhile exercise.
"No one is ever 100 percent prepared for any disaster or any emergency but if we can only be talking better to each other and be prepared for the various contingencies of often mechanical breakdowns of things and the like then we'll be better serving and people will be safer for it," he said.
The deadly H5N1 strain of avian flu has killed more than 125 people around the world since it reappeared in late 2003. Most of the victims have been in Asia.
APEC members Indonesia and Vietnam have been hardest hit.
The virus so far is most dangerous to birds, and it has killed or led to the culling of more than 200 million chickens, ducks and geese around the world.
Most human victims caught the virus from sick birds, but scientists fear H5N1 could evolve into a virus that passes easily from person to person, triggering a pandemic that could kill millions.