"The results, showing an engineered flu strain can spread easily between ferrets, derive from a controversial study that stirred debate over fears of a bioterrorism threat."
"In a long-awaited study that helped prompt a contentious debate over the wisdom of conducting research that has the potential to help as well as harm, scientists reported Wednesday that they had engineered a mutant strain of bird flu that can spread easily between ferrets — a laboratory animal that responds to flu viruses much as people do.
That means that bird flu has "the potential to acquire the ability to transmit in mammals," said University of Wisconsin virologist Yoshihiro Kawaoka, who led the study.
Only a few mutations were necessary for the transformation, he added, which suggests that a more contagious strain of bird flu could emerge on its own without targeted prodding by scientists in the lab.
Kawaoka's discovery, published online after a months-long delay by the journal Nature, dampens hopes that the deadly H5N1 virus simply wasn't capable of becoming a highly contagious bug in mammals, including humans."
Eryn Brown reports for the Los Angeles Times May 3, 2012.