Worries about bird flu have overtaken a regional economic summit in Bangkok this week by heads of government from Cambodia, Laos, Burma, Thailand, and Vietnam.

The 7-year-old boy, Ronnarit, is suspected of having bird flu and is hospitalized at hospital in Bangkok, Oct 21, 2005

The five government chiefs' two days of meetings begin Wednesday as health authorities across Southeast Asia battle to contain a spreading bird flu outbreak. The virus has ravaged poultry flocks, and there are fears it will claim more human lives in the winter months ahead.

This week's summit is the second top-level meeting of the regional group known as ACSMECS. The organization focuses on economic cooperation and strategy.  Its name is based on the three major river systems that flow through the area:  the Ayeyawady, Chao Phraya and Mekong.

Thai Prime Minister Thaksin Shinawatra says fighting the avian flu virus will be a key topic at the summit. Thailand, Cambodia, and Vietnam have been hit the hardest by the H5N1 strain of bird flu that has killed more than 60 people in Asia.

Thai Foreign Ministry spokesman Sihasak Phuangketkeow says the leaders will be looking to improve cooperation in dealing with bird flu.

"That is the common challenge that we face - not just the countries within ACMECS but countries in the region and international community," he said. "Certainly we think it is time for us to work together, to pool our resources to deal with the challenge of the bird flu before it becomes a real crisis."

Avian flu virus carried by migratory birds has spread into Russia and Europe. Given the serious challenge the virus poses, Mr. Sihasak says regional leaders at the Bangkok summit hope to intensify their links with the international community.

Vietnam in particular is seeking more international assistance for its efforts to control bird flu.

ACMECS also has a wider role in promoting regional economic development. The five member states also are part of the Association of South East Asian Nations. But Vietnam, Laos, Cambodia and Burma, who are among ASEAN's newest members, face greater development challenges than Thailand, Malaysia or Singapore.

Mr. Sihasak says this week's meeting will further explore opportunities to bridge the gap between ACMECS and ASEAN nations. "ACMECS has as one of its principal benefits to reduce the development gap in the region, and this will help to move forward the integration within the broader ASEAN framework," he added.

Thailand is looking to increase trade in agricultural commodities, with an aim of developing contract farming programs with other member countries.

ACMECS is committed to strengthening regional trade and investment, agricultural and industrial cooperation, transport links, tourism, and human resources development.