By Nathan Gill and James Attwood

Aug. 21 (Bloomberg) — Two Chilean poultry farms are under quarantine after swine flu was detected in turkeys, the first case of the virus found in birds, the nation’s health ministry and U.S. health officials said.

Sopraval SA, the Santiago-based producer of poultry, beef and pork products, said agricultural authorities identified the virus, also known as H1N1, in turkeys on two of the company’s farms, it wrote in a statement posted today on the Web site of Chile’s securities regulator. Sopraval is working with authorities to prevent the spread of the flu, it said.

The flu was identified after workers noticed a drop in egg production, said Jay Butler, director of the H1N1 task force for the U.S. Centers for Disease Control and Prevention in Atlanta. The genetic makeup of H1N1 enables the virus to be carried in birds, he said. While the infections aren’t surprising, he said scientists are concerned the virus may combine with the H5N1 bird flu virus, which kills half the humans that get it.

Genetic combination of the two viruses “has not been documented, but that is certainly a concern if a bird is co-infected with both strains,” Butler said today in a conference call with reporters. “That’s a theoretical possibility that we’ve known existed.”

Preliminary studies by Chile’s Public Health Institute showed that turkeys in the South American country’s Valparaiso Region were infected with the swine flu virus, Carlos Pavletic, a Chilean health ministry official, said today to reporters in Santiago.

First Case

“This is the first situation reported of birds being infected with swine flu in the world,” Pavletic said. “The sequencing analyses that the institute is performing right now will probably be finished tomorrow.”

The bird infections, if confirmed, don’t represent a threat to humans, Pavletic said. Initial tests also ruled out the presence of H5N1, Sopraval said in the statement.

Swine flu, which causes similar symptoms as seasonal influenza strains, has swept across the globe faster than any other pandemic flu, reaching more than 170 countries and territories in the four months since being identified, the World Health Organization said.

The H5N1 bird flu virus, which isn’t easily transmitted among people, has killed 61 percent of the 432 people infected since 2003, according to the WHO.