The government advisory board that oversees biosecurity in the U.S. is asking the scientific journals Nature and Science to censor details of recent studies on bird flu due to concerns about biological terrorism. Researchers created mutations of the A(H5N1) virus, making it transferable between mammals through the air. In 60 percent of human cases, this strain of avian flu is fatal. At present, only 350 people worldwide have died because of the flu, only because it can be contracted via direct contact with infected birds. D. A. Henderson, professor of medicine and founder of the Center for Biosecurity at the University of Pittsburgh Medical Center, and Christine Gorman, senior editor for health and medicine at Scientific American, discuss whether it is appropriate for the government to ask science journals to censor content.