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An unexpected big drop in new U.S. tuberculosis cases is probably because of stepped up screening and treatment of immigrants before they leave their native countries, health officials say.
The nation's largest association of doctors and the AARP senior citizens' lobby are endorsing President Barack Obama's revised health overhaul legislation.
In a March 18 story about drug-resistant tuberculosis, The Associated Press reported erroneously that there were no U.S. cases in 2008 of extensively drug-resistant TB. There were four cases in 2008 and no cases in 2009, according to the Centers for Disease Control and Prevention.