Bird flu studies at the centre of a heated controversy pose a potential risk to public health of an "unusually high magnitude," the U.S. biosecurity experts who have advised against full publication of the studies said Tuesday.
The U.S. National Science Advisory Board on Biosecurity said emergence of an H5N1 flu virus capable of spreading easily from person to person would be an "unimaginable catastrophe" regardless of whether it was concocted by nature or in a laboratory.
The comments are part of a statement from the 23-member group outlining, for the first time in published form, their rationale for advising the U.S. government to ask the journals Science and Nature to withhold key sections of the two studies.
The journals and the research teams have tentatively agreed to publish only the findings, if a system can be established to share details of the methods used with researchers and public-health agents on a need-to-know basis.
"We do not believe that widespread dissemination of the methodology in this case is a responsible action," the NSABB members argued in a commentary published in the two journals.
The position was supported by renowned flu expert Robert Webster, who is not a member of the NSABB.
In a commentary published in the journal mBio, Webster — from St. Jude Children's Research Hospital in Memphis, Tenn. — acknowledged that the withheld information will likely leak out but said he still doesn't think detailed methods of the studies should be published. That said, Webster said he believes work on H5N1 transmission should continue.
The NSABB statement contained little in the way of new insight, though it is hard to imagine how the group could be specific about their concerns without releasing information they insist does not belong in the public domain.
Acting board chair Paul Keim, an anthrax expert, did not immediately respond to a request for an interview Tuesday. However, a question-and-answer style interview Nature conducted with him provides a deeper understanding of the board's thinking.
It reveals the NSABB is concerned the two laboratories that conducted the disputed studies have created H5N1 viruses — or hybrids containing some H5N1 genes — that bypass what have seemed to have been natural barriers to H5N1's ability to spread easily in mammals.
(Both groups did work in ferrets, the animal model considered the best for predicting how a flu virus will behave in humans. There is no way to be sure that a virus that spreads easily among ferrets will also do so among people, but it would be unsafe and unethical to test the lab-made viruses in people.)
Keim noted that the H5N1 virus has been around since at least 1996 and hasn't yet mutated to be able to spread easily from person to person, perhaps because of "inherent biological limitations."
Some flu researchers have speculated for decades that some influenza virus subtypes cannot successfully adapt to spread in humans.
But science cannot currently explain why some flu viruses emerge from nature to successfully infect humans and others do not. Nor can it say that a virus that has not yet made the leap will never be able to do so. If flu viruses have barriers or timetables, they haven't shared that information yet with humans.
The current controversy relates to research conducted to try to chip away at those questions as they relate to H5N1 viruses. The work was done at Erasmus Medical Centre in Rotterdam, the Netherlands, and at the University of Wisconsin-Madison.
The Dutch work, led by virologist Ron Fouchier, produced a mutated H5N1 virus that spread by the respiratory route — the equivalent of coughing and sneezing — in ferrets. The virus was lethal to all the ferrets, though Fouchier cautioned that the dose of virus used was high and may not reflect what would be seen with natural infection.
The American team, led by virologist Yoshihiro Kawaoka, produced what's known as a reassortant, a virus containing the hemagglutinin (the H in a flu virus's name) from an H5N1 virus and the seven remaining genes from the H1N1 virus that caused the 2009 pandemic. That hybrid virus did not kill ferrets.
Fouchier, who objects to the NSABB's position and has been waiting to read the group's rationale, was disappointed by the published statement.
"I was hoping for an explanation of the risks of communicating the results of our study via normal publication. There is none," he said in an email.
"Our information is useless to small bioterrorist groups, and larger organizations and rogue countries can replicate our work without our manuscript."
Fouchier said based on the points made in the Nature interview with Keim, several previously published flu studies should not have made it into print. And he worried that the thinking could lead to more frequent demands for redacting manuscripts in future.
Flu scientists, led by Fouchier, announced recently that they will observe a voluntary two-month moratorium on H5N1 transmission studies. One of the journals — Science — has agreed to hold off publication until March. Nature is not commenting on its plans.
The idea is to allow international talks on resolving the dispute to get underway. The World Health Organization is facilitating those talks, and has called a small meeting of the research teams, some leading flu experts, the journal editors and a few other key players for Feb. 16 and 17.
The WHO, which has taken the lead on the first meeting, at this point will not disclose the names of the people being invited. Dr. Keiji Fukuda, the WHO's point person for the meeting, said the attendance is still being worked out but once it is finalized the agency will post a list of those who will be attending.
The meeting will be held behind closed doors. "Some of the things that we're discussing are considered sensitive, which is why we are having this first meeting to focus on the specifics. What exactly are the facts? What exactly is sensitive? Why is it sensitive?" Fukuda explained.
More far-reaching issues raised by the controversy will likely be explored at another larger meeting later, Fukuda said, noting that this small meeting cannot undertake to set policy, given that there won't be a broad group of people in the room.