Three cats have tested positive for the deadly strain of bird flu in Austria's first reported case of the disease spreading to an animal other than a bird, state authorities said Monday.
The sick cats were among 170 living at an animal shelter where the disease was detected in chickens last month, authorities said.
The World Health Organization called bird flu a greater global challenge than any previous infectious disease, costing global agriculture more than $10 billion and affecting the livelihoods of 300 million farmers.
Meanwhile, U.S. health officials announced plans for a second vaccine to protect people from bird flu because the virus that is spreading among birds in Asia and Europe has changed significantly in the past year.
The government has several million doses of an earlier bird flu vaccine, but it was based on a sample of virus taken from Vietnam in 2004.
The germ is believed to have mutated enough since then that the form now circulating in Africa and Europe may be different, health officials said.
U.S. Health and Human Services Secretary Mike Leavitt said Monday he had authorized the National Institutes of Health and the federal Centers for Disease Control and Prevention to begin working on a second vaccine for humans.
In other developments:A top animal health official with the Rome-based U.N. Food and Agriculture Organization said developed countries had responded slowly to bird flu, failing to control the disease in Asia and not doing enough to prepare poor countries, particularly in Africa, for its spread. "In 2004 we said it will be an international crisis if we don't stop it in Asia, and this is exactly what is happening two years later," said Joseph Domenech, head of the agency's Animal Health Service.Four wild ducks found in southern Sweden have tested positive for an aggressive strain of bird flu, authorities said Monday. Tests confirmed the birds carried a highly pathogenic virus of the H5 type, but it was not immediately clear whether it was the deadly H5N1 strain, the National Veterinary Institute said. Two other wild ducks found in the same area near the southeastern coastal city of Oskarshamn, about 150 miles south of Stockholm, tested positive for the same virus last week.Some cat owners in France were panicking last Wednesday that their pets might catch lethal bird flu, bombarding the animal protection society with anxious calls after a dead cat in Germany tested positive for the lethal H5N1 strain of avian influenza.According to the latest WHO figures, the H5N1 strain has killed at least 95 people since 2003, mostly in Asia, and devastated poultry stocks. Scientists are concerned that the virus could mutate into a form easily spread between people, sparking a pandemic.
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