In Europe, add Portugal to the list of countries with confirmed or suspected cases of the highly contagious disease, which affects livestock and can be spread on clothing or by the wind. And in South America, an outbreak was confirmed in Argentina. CBS's Wyatt Andrews is tracking urgent efforts to keep foot-and-mouth from spreading to this country.
When Virgin Atlantic flight 21 arrived in Washington today from England, US Agriculture inspectors took David Owitz's shoes. Then they disinfected them in bleach. As part of a heightened state of alert, passengers from Europe and South America are now being targeted for scrutiny.
As they step off the plane, passengers are being asked if they've been on a farm. Those who have find themselves being disinfected. In addition, the official US welcome includes having dogs sniff their luggage. Owitz was understanding.
"It's absolutely fair enough," Owitz says.
US officials say the precautions are necessary to keep foot-and-mouth out of the country. While the disease is not at all harmful to humans, it is horrifically contagious to sheep, pigs and cattle.
"We are extremely concerned because we know how quickly and rapidly this virus can spread. In two to four days, it can be all over the place," says Dr. Craig Reed of the US Department of Agriculture.
No US farm has faced a foot-and-mouth outbreak for 72 years, but that hasn't stopped the fear of the disease. Once a single animal has been infected, the only remedy is the destruction of the herd.
That's the reason livestock farmers and ranchers across the country welcome the official state of alert.
Farmers say we have to do everything that we can to make sure that the disease doesn't get into this country, because it would be devastating to our cattle, causing weight loss and killing calves.
Officials stress there is no threat to human health, either from animals or from food. Still, for farmers who sell and export livestock, even the first case of foot-and-mouth could harm consumer confidence and cost billions.
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