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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An artist on Rio de Janeiro's Copacabana beach puts the final touches on a sand sculpture of the kissing bug, which spreads Chagas' disease. The sculpture was part of an event in 2009 commemorating the 100th anniversary of the discovery of the disease.
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