International scientists are resuming some high-stakes research with the deadly bird flu, after a year-long pause.
An outcry erupted when scientists in the Netherlands and the U.S. reported they had created easier-to-spread versions of the virus.
They were studying how bird flu might mutate to become a bigger threat to people. But critics worried about safety precautions, and whether the work might aid terrorists.
So last January, those scientists and three dozen more, including some of the world's leading flu specialists, temporarily halted this kind of research.
On Wednesday, the scientists said it's time to get back to work since health authorities have come up with new rules to oversee the research. A number of countries already have issued them, and the U.S. is finalizing its own guidelines.