One of two controversial papers describing how the avian H5N1 influenza virus could become transmissible in mammals was published yesterday, after months of global debate.
The study, from the University of Wisconsin-Madison, shows that the bird flu virus can, with just a few genetic mutations, take a form that can pass easily between ferrets.
"Our study shows that relatively few amino acid mutations are sufficient for a virus with an avian H5 hemagglutinin to acquire the ability to transmit in mammals," says researcher Yoshihiro Kawaoka.
"This study has significant public health benefits and contributes to our understanding of this important pathogen. By identifying mutations that facilitate transmission among mammals, those whose job it is to monitor viruses circulating in nature can look for these mutations so measures can be taken to effectively protect human health."
But critics were concerned that publishing the work could enable potential bioterrorists. As a result, the paper, along with another related piece of research, was held back from publication following a review from the National Science Advisory Board for Biosecurity, which recommended that much of the information be redacted.
Now, though, it's reversed its decision on the grounds that there's a good health rationale for the work, and after seeing more evidence about the security of the facilities where it was carried out.
Kawaoka is pleased with this conclusion, pointing out that other unknown mutations could also enable the virus to transmit in mammals, and these should be identified.
"The additional mutations may emerge as the virus continues to circulate," he says.
"Should surveillance activities identify flu strains accumulating additional key mutations, these emerging viruses should then be priority candidates for vaccine development and antiviral evaluation."
The report appears in Nature.
"As far as Nature is aware, formal assessments by security agencies have led to recommendations that the Kawaoka paper be published. This includes an independent assessment that we commissioned from a non-US biological-defence agency, whose advice can be found at go.nature.com/wglsea," it says in an editorial.
"In subsequent discussions with biosecurity researchers, there has been a striking unanimity: where there is a benefit to public health or science, publish! It has been enlightening to see how scientists in this secretive arena see the open scientific enterprise as their best recourse in times of potential trouble."