ROME (Reuters) - Poultry producers have been saddled with enormous costs due to recent outbreaks of the deadly bird flu virus, veterinary experts of the Food and Agriculture Organization (FAO) said on Wednesday.

Avian influenza remains essentially an animal disease. But the H5N1 virus has killed 127 people since it re-emerged in Asia in late 2003, the World Health Organization (WHO) has said.

"It has a huge economic impact," FAO Chief of Animal Health Services Joseph Domenech told a news conference.

"The cost is very, very huge," he added, when asked about how much the recent outbreak of the virus, moving into parts of the Middle East, Europe and Africa, cost the poultry sector.

Domenech could not quantify the costs and it was hard to estimate as the poultry sector varied greatly in different regions, from backyard farming in Africa to highly industrialized production in Europe.

Juan Lubroth, head of the FAO´s emergency prevention system, told reporters after the news conference that Thailand had lost $1.2 billion in trade with the European Union overnight when the country declared it had a bird-flu outbreak.

EU Agriculture Commissioner Mariann Fischer Boel said on Tuesday that most EU member states have requested subsidies from Brussels to boost consumer confidence in poultry, hit hard by bird-flu fears.

FAO experts said it was to difficult to forecast a recovery for poultry this year or 2007 because the spread of the virus was unpredictable.

Domenech said control of bird flu was in general good in Europe, has improved in Asia compared with two years ago and was worrying in Africa because of lack of funds there.