Thailand has detected bird flu in the sixth province since the virus reappeared in the country this year, after dead fighting cocks and egg-laying chickens tested positive for the H5N1 strain, the government said.

Tests on 204 egg-laying chickens and four fighting cocks that died last week in Nong Khai province, 615 kilometers (384 miles) northeast of the capital, Bangkok, showed them to have been infected with the H5N1 strain of avian influenza, Thailand´s Department of Livestock Development said on its Web site.

Bird flu will remain a threat in Asia for years and may worsen in the wake of the tsunami disaster, United Nations and Paris-based agencies said in a joint statement on Feb. 1.

``The disease will be present for several years in the countries that experienced outbreaks during 2004,创 the Paris based World Animal Health Organization and the United Nations Food and Agriculture Organization in Rome said in the statement.

The Dec. 26 earthquake and tsunami that destroyed coastal areas in 12 countries in the Indian Ocean led to ``large-scale movement of poultry创 that may spread the avian influenza virus, according to the two agencies.

Thailand, Asia´s second-biggest poultry exporter, on Feb. 1 resumed nationwide testing of poultry for avian influenza in an effort to prevent an epidemic amid rising human deaths from the virus in nearby Vietnam. That country on Jan. 31 reported its 12th human fatality from the virus since December.

Thailand last year confirmed 12 human deaths from the avian influenza virus. The previous outbreak was contained in October after the government ordered the checking and killing of poultry suspected of infection.