A old osteoporosis drug may be effective in killing a range of influenza viruses, including ones that are very dangerous to people like the H5N1 bird flu virus, scientists in Hong Kong reported on Wednesday.Unlike antiviral drugs that target and mute flu viruses, the drug pamidronate boosts a certain class of human immune cells and sets them off on a killing spree to exterminate host cells that are infected with flu viruses.
