As U.N. Food and Agricultural Organization concluded, there is no evidence linking pigs to the bird flu outbreak. Countries should focus their efforts on chickens and other fowl, FAO said Tuesday.
The agency's comments raise questions about Indonesia's decision to cull 18 pigs over the weekend, claiming they had tested positive for the H5N1 strain of the virus.
Agriculture Minister Anton Apriyantono has said the slaughter of infected pigs will continue.
"We have no evidence to show the pigs are contributing to the avian flu epidemic either in Indonesia, Vietnam or Thailand ... so the focus should be on chickens and ducks," Dr. Juan Lubroth, a veterinary with the FAO, said in a telephone interview from Rome.
"There is some historical data from China and Vietnam as well as Indonesia where this particular virus has been identified in pigs," he said. "But we don't have evidence that the pigs were diseased or were actually infected by the virus."
Meanwhile, the country's top veterinarian came out against the Agriculture Ministry policy, saying it appeared to be "political." Indonesia is the world's most populous Islamic country and many Muslims consider pigs to be unclean.
"There is no proof that any humans have been infected by pigs," said Dr. Trisatya Putri Naipospos, adding "we have to control the disease at the source, and the source is birds and chickens infected by the H5N1 virus, not pigs."
Bird flu has swept through poultry populations in large swaths of Asia since 2003, killing or forcing the slaughter of hundreds of millions of ducks and chickens. It also jumped to humans, killing 57 regionwide, most of them in Vietnam and Thailand.
Experts worry that pigs infected with both bird flu and its human equivalent could act as a "mixing bowl," resulting in a more dangerous, mutant virus that might spread to people more easily - and then from person to person, reports the AP.
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