The U.S. journal Science on Thursday published the results of a controversial study in which researchers at the Erasmus Medical Center in the Netherlands "identified five mutations apparently necessary to make the [H5N1] bird flu virus spread easily among ferrets, which catch the same flus that humans do," the New York Times reports (McNeil, 6/21). "The publication of [the] research had been delayed by several months after the U.S. government's National Science Advisory Board for Biosecurity (NSABB) warned that the information should be censored to avoid being misused, for example by terrorists," the Guardian writes, noting, "Last month, Yoshihiro Kawaoka at the University of Wisconsin-Madison published details of another form of the bird flu virus that can pass between people, which was created by merging a mutated strain with the swine flu virus that sparked a human pandemic in 2009" (Jha, 6/21).