The United States Government has taken the unprecedented step of asking scientists to censor key parts of their work describing how they managed to mutate the H5N1 bird flu virus into a strain that could be highly infectious and deadly to humans.

US government officials have become so alarmed at the prospect of the information falling into the hands of terrorists intent on making a biological weapon that they have asked for critical details of the experiments to be deleted from scientific manuscripts before being published.

Two groups of scientists, in the Netherlands and the US, have submitted scientific papers to the journals Nature and Science describing how they have managed to convert the bird flu virus, which does not spread easily between people, into an airborne form that can be transmitted in coughs and sneezes.

As The Independent revealed yesterday, a group of special scientific advisors to the US Government decided that the details of the two studies into H5N1 bird flu were too sensitive to be published in full and recommended redactions to the manuscripts rather than a complete ban on publication.

In a statement released yesterday, the US National Institutes of Health (NIH), which funded the research, said that many scientists and public health officials are concerned that the virus could evolve naturally into a form that is transmissible between humans, which could result in a devastating pandemic.

H5N1 Virus

“While the public health benefits of such research can be important, certain information obtained through such studies has the potential to be misused for harmful purposes,” the statement says. “These manuscripts… concluded that the H5N1 virus has greater potential than previously believed to gain a dangerous capacity to be transmitted among mammals, including perhaps humans.”

The NIH said the US National Science Advisory Board for Biosecurity, which advises the US Government, recommended that the scientists and the two journals should omit key details of experiments. It does not want the publication of all the scientific methods used in the experiments, nor the genetic sequences of the mutated H5N1 virus, in order to prevent replication of the research “by those who would seek to do harm”.

Ron Fouchier, a virologist at the Erasmus Medical Centre in Rotterdam, deliberately mutated the bird flu virus prior to passing it from one group of experimental ferrets to another, which led to a total of five mutations in two genes that allowed the virus to spread in the air. His work was submitted to Science, while the manuscript of a similar study carried out by Yoshihiro Kawaoka of Wisconsin and Tokyo universities was submitted to Nature.

While being supportive of measures designed to prevent research details falling into the wrong hands, Bruce Alberts, editor-in-chief of Science, and Philip Campbell, editor-in-chief of Nature, spoke of concerns about withholding potentially important public health information from responsible influenza researchers who need to know the details to protect the public.