Health officials around the world are on constant lookout for the deadly bird flu. Here a worker collects chickens on a farm in Kathamndu, Nepal, where the virus was suspected of infecting poultry last October.
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A worker makes a cut in the side of a sandstone block at the Cleveland Quarries facility in Vermilion, Ohio, earlier this month. The legal limit on the amount of silica that workers can inhale was set decades ago.
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Two chimps groom each other at the Save the Chimps facility in Florida. The National Institutes of Health owns about 360 chimpanzees that aren't yet retired and that are living at research facilities; new guidelines say most of its chimps should be retired.
Save the Chimps
Researchers at the U.S. Geological Survey National Wildlife Health Center in Madison, Wis., use eggs to see if the Asian strain of the H5N1 bird flu virus has entered the U.S. in this photo from 2006.
A health official culls chickens on a poultry farm in a village on the outskirts of Katmandu, Nepal. Chickens suspected of being infected with H5N1 bird flu were found in the area in October.
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A prefectural officer carries a chicken on a poultry farm on Oct. 15 on the outskirts of Kathmandu, Nepal, where chickens suspected of being infected with bird flu were found.
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