NSABB speaks out on weaponized H5N1 flap

The core of the U.S. biosecurity advisory board's unease about two unpublished, controversial H5N1 virus studies is that they have demonstrated how to remove the natural barrier preventing viruses from spreading efficiently in mammals.

By removing the barrier, these mutant viruses could be released by bioterrorists or by accident to cause a catastrophic pandemic. The board recommended withholding details of the studies from being published, CIDRAP News reports.

"The artificial evolution of a new mammal-adapted H5N1 virus, as reported in these two papers, has removed the natural barriers that might have existed," Paul Keim, the acting chair of the NSABB, said, according to CIDRAP News. "Accomplishing this in the lab, however, doesn't mean that it can occur naturally."

The NSABB members found that while the studies were dangerous from a bioterrorism standpoint, they were very valuable. The statements the board published on Tuesday were the first formal statements it had made since the recommendation against full publication was announced on December 20.

"(The two studies are) very important because, before these experiments were done, it was uncertain whether avian influenza A/H5N1 could ever acquire the capacity for mammal-to-mammal transmission," the NSABB said, according to CIDRAP News. "Now that this information is known, society can take steps globally to prepare for when nature might generate such a virus spontaneously."

Part of the interview with Keim focused on why Yoshihiro Kawaoka's study was included in the recommendation because it involves a virus that was not lethal in ferrets and was a reassortant rather than a specifically H5N1 strain.

"The fact that Kawaoka's specific virus and mutations might not be the feared H5N1 pandemic strain is not the point," Keim said, according to CIDRAP News. "It is that this laboratory created a virus that has now bypassed apparent barriers to evolution in the wild. If this virus were to escape by error or by terror, we must ask whether it would cause a pandemic. The probability is unknown, but it is not zero."

Ron Fouchier of the Erasmus Medical Center in Rotterdam, the leader of the other study, was disappointed in the explanations given by the NSABB on Tuesday.

"I was hoping for an explanation of the risks of communicating the results of our study via normal publication," Fouchier said, according to Canadian Press. "There is none. Our information is useless to small bioterrorist groups, and larger organizations and rogue countries can replicate our work without our manuscript."