Scientists and security specialists are in the midst of a fierce debate over recent experiments on a strain of bird flu virus that made it more contagious.
The big question: Should the results be made public?
Critics say doing so could potentially reveal how to make powerful new bioweapons.
The H5N1 virus has been circulating among birds and other animals in recent years. It's also infected about 500 people. More than half died. But this dangerous virus has not caused widespread human disease because, so far, sick people haven't been very contagious.