The swine flu recently detected in turkeys in Chile may spread to other poultry, the United Nations said in urging greater monitoring worldwide to prevent the virus from combining with the deadlier H5N1 strain of bird flu.

The UN's Food and Agriculture Organization said Thursday developing countries in particular need better ways to respond in case a combination of the two flu viruses emerges. Experts think it would be unlikely for swine flu to swap genes with H5N1 bird flu but, since flu viruses are unpredictable, they cannot rule out the possibility.

'In Southeast Asia, where there is a lot of the virus circulating in poultry, the introduction of H1N1 in these populations would be of greater concern.'— Juan Lubroth

The UN said it would be greatly concerned if swine flu were to combine with bird flu, which isn't as contagious but is far more deadly.

Last week, Chile announced swine flu had jumped to turkeys, raising new concerns about the ability of the virus to infect other species. That gives swine flu more opportunities to mutate into a more dangerous form.

Officials stressed the birds had suffered only mild symptoms and were being allowed to recover rather than be culled.

No H5N1 bird flu in Chile

The Food and Agriculture Organization warned swine flu could spread to other poultry farms around the world.

The organization's interim chief veterinary officer, Juan Lubroth, noted that Chile at present doesn't have H5N1 bird flu. "In Southeast Asia, where there is a lot of the virus circulating in poultry, the introduction of H1N1 in these populations would be of greater concern."

The organization is calling for better monitoring of animals and better hygienic practices at farms to keep infected animals from farm workers and vice versa.

Chile was the fourth country to report a spillover of swine flu from farm workers showing flulike symptoms to animals, following Canada, Argentina and Australia, the Food and Agriculture Organization said.

The organization stressed that the discovery of swine flu in turkeys doesn't pose an immediate threat to humans and that turkey meat can still be sold commercially following proper inspections.

Swine flu was declared to be a pandemic, or global outbreak, by the World Health Organization in June, and it is expected to make a strong return in the fall and winter. The WHO has said the virus has killed at least 1,800 people worldwide.