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Possible Bird Flu Found In U.S.

bird flu generic: Chickens over H5N1 strain of bird flu virus, seen under microscope
AP / CBS
Scientists have discovered the possible presence of bird flu in wild mute swans in the upper Midwest state of Michigan, but it does not appear to be the most worrisome, highly pathogenic strain, the White House announced Monday.

"They believe it is a strain of low pathogenicity, similar to strains that have been seen before in North America," White House spokesman Tony Snow said.

Testing is still being done to confirm the presence of the H5N1 virus and its type. Officials with the Agriculture and Interior departments were to announce details later Monday morning.

Scientists had feared that the deadly H5N1 strain of bird flu would reach North America, in birds, sometime this year. Just last week, the U.S. expanded monitoring of wild migratory birds throughout the nation, to check for early warning signs.

However, health officials stress that the virus' appearance in wild birds would not be a public health crisis, especially if it were the less worrisome, low-pathogenic strain.

The H5N1 virus has killed at least 138 people worldwide since it began ravaging Asian poultry stocks in late 2003. But virtually all caught the virus from close contact with sick birds or their droppings.

Health officials are closely watching H5N1's march around the globe for fear the virus eventually could mutate into a strain that could spread easily from person-to-person, possibly sparking a worldwide epidemic. No one knows how likely that is to happen, and specialists agree that the risk doesn't jump even if a few infected birds are found to have entered the U.S.

But if that happens, it could trigger additional security steps, especially to prevent wild birds from infecting U.S. poultry flocks, and more stringent monitoring.

Wild birds, especially waterfowl, carry a multitude of flu viruses — and officials have repeatedly warned that this first batch of testing could produce a lot of false alarms.

Only confirmatory tests that will take several more days, possibly up to 10, can tell whether a suspect bird really has H5N1 or some other harmless flu strain. If so, that testing also will confirm whether the virus is the so-called "high-pathogenic" version, the deadly type, or a so-called "low-pathogenic" version, a mild type not of concern for humans.

In Related Developments

  • A farmer has died of bird flu in far western China, the 14th person to die of the disease in the country. The Health Ministry confirmed the 62-year-old farmer in the Xinjiang region died July 12 of the H5N1 strain of bird flu, the official Xinhua News Agency said. The case brings China's total number of human bird flu infections to 21, Xinhua said.
  • Indonesia's latest bird flu patient checked out of hospital after spending just a night there, while his cousin died last week showing symptoms of the virus but was not tested in time, health officials said Monday. Umar Aup was admitted to a hospital in west Java province last Wednesday and left the next day on the orders of his family, who said they could treat him at home with a mixture of prayers and traditional remedies, said Dr. Eka Sony, a Health Ministry official investigating the case.
  • The H5N1 virus has killed at least 138 people worldwide since it began ravaging Asian poultry stocks in late 2003, according to a tally kept by the World Health Organization.