"Two teams of researchers who have engineered deadly and pathogenic flu viruses have reluctantly agreed to withhold vital details of their work for national-security reasons -- the first time any scientific team has been asked to do so."
"The experts, who are among the top flu researchers in the world, agreed to publish the results of their controversial experiments but not the details of what they did. Albert Osterhaus of Erasmus Medical Center in the Netherlands wrote one study to be published in the journal Science; Yoshihiro Kawaoka of the University of Wisconsin conducted the other, to be published in the rival journal Nature.
'This is unprecedented,' Osterhaus told Science."
Maggie Fox reports for the National Journal December 20, 2011.