May 8, 2009

USDA scientists are working to create a specific screening test to detect the A/H1N1 flu virus in US swine, USDA Secretary Tom Vilsack said Thursday (May 7).

Swine flu is a common occurrence in pigs in the US, but the new A/H1N1 flu contains swine, avian and human viral genes and can be deadly for humans. It has sickened or killed people in Mexico, the U.S. and Canada, but it wasn't actually found in swine until this past weekend, when it was confirmed in pigs and humans at a Canadian farm.

The US produces about 23 billion pounds of pork per year and the health of the herd is paramount to producers and the USDA.

"We are growing virus to meet potential future diagnostic needs and determining if USDA can detect this strain with the screening test we currently use to detect bird flu," Vilsack told lawmakers Thursday in testimony provided to a Senate Appropriations subcommittee.

As of now, Vilsack said, he has asked laboratories that do routine swine flu testing to send in to USDA's National Veterinary Services Laboratories any virus samples that are difficult to determine what the subtype and are suspect as possibly A/H1N1.

"If we were to detect an unusual case of swine flu, USDA would take a series of swift and appropriate actions to contain the virus and protect animal and human health while the virus was being identified," Vilsack said.

And if any "unusual" swine flu turns out to be the A/H1N1 flu, Vilsack said, the USDA would immediately try to determine how wide the infection had spread.

One unknown, though, Vilsack said, is how quickly the virus can spread between pigs. The USDA is already conducting experiments to see how easily the animals can spread it amongst themselves, he said, and that information "will be crucial for the US swine industry to prepare for infection of swine herds with the new virus."