Interior Secretary Gale Norton told reporters, "It is increasingly likely that we will detect the highly pathogenic H5N1 strain of avian flu in birds within the U.S. borders possibly as early as this year."
Norton, Agriculture Secretary Mike Johanns and Secretary of Health and Human Services Michael Leavitt unveiled a plan to increase monitoring of migratory birds that could bring the virus to the United States. The plan includes expanding the government's early warning system, particularly in Alaska where migratory birds would most likely arrive.
"None of us can build a cage around the United States," Johanns said, according to a Reuters report. "We have to be prepared to deal with the virus here."
Officials in several countries across Europe, Africa and Asia have detected the H5N1 virus in birds and humans. The virus has killed at least 98 people worldwide since 2003, including the latest victim, a 30-year-old woman in Egypt, Egyptian authorities announced Saturday. The death of the woman, from Qaloubiyah province some 25 miles north of Cairo, marked the country's first bird flu casualty, Reuters reported.
Bird flu victims contract the virus by contact with infected birds. Health officials estimate the virus' mortality rate at 50 percent, although diagnosis inconsistencies make an accurate assessment difficult.
Scientists fear the virus could mutate and develop the ability to move from human to human, a significant development that could devastate the global economy and spark a worldwide pandemic that could kill millions.
Already, the H5N1 strain in humans has evolved into two separate strains, U.S. researchers reported Monday.
"Back in 2003 we only had one genetically distinct population of H5N1 with the potential to cause a human pandemic. Now we have two," U.S. Centers for Disease Control and Prevention researcher Rebecca Garten told colleagues at the International Conference on Emerging Infectious Diseases in Atlanta.
U.S. officials said Americans should not panic if the virus is discovered in the United States.
"Our producers have demonstrated that they will call us at the first sign of sick birds," Johanns said. "This is a $29 billion industry in the U.S. and our producers are as eager as we are to protect the safety of our poultry."
Johanns said the government would reimburse producers for any birds that have to be destroyed.
Also Monday, Israeli officials poisoned hundreds of chickens and turkeys in an effort to contain a fast-spreading outbreak of the virus.
And in London, British government officials warned that the virus could arrive in Britain, which so far has been spared, as early as August or September.