Results from a controversial research project in which scientists created a pandemic strain of the deadly H5N1 bird flu virus in the lab were finally published on Thursday, after an eight-month delay while scientists and biosecurity officials debated how much of the information should be made public.
Scientists wanted to know what changes in the H5N1 virus, which cannot currently spread between people, were necessary for it to become transmissible through the air via coughs and sneezes. They genetically modified the wild H5N1 virus and found that it would only require mutations at five locations in its genome for a pandemic strain to emerge.
Ron Fouchier, Professor of Molecular Virology in the Department of Virology at Erasmus Medical Center in the Netherlands, led the team of scientists who created the virus. They genetically altered the wild H5N1 virus at three locations and then used it to infect ferrets – the standard model used to mimic flu in humans. As the virus spread between the animals by physical contact, it picked up additional mutations until, with only five mutations to differentiate it from the wild virus, it became airborne and able to spread via the kind of tiny droplets produced in a cough or sneeze.
The results of Fouchier's experiment was published in the journal Science's edition for Thursday, June 21, 2012.
Last month, Yoshihiro Kawaoka, at the University of Wisconsin-Madison, published details of another form of the bird flu virus that can pass between people, which was created by merging a mutated strain with the swine flu virus that sparked a human pandemic in 2009.
The publication of both Kawaoka and Fouchier's research had been delayed by several months after the U.S. government's National Science Advisory Board for Biosecurity (NSABB) warned that the information should be censored to avoid being misused, for example by terrorists. Scientists argued that the research should be published in full so that they and public health authorities would be prepared with vaccines and public health protocols if the wild strain of H5N1 naturally mutated into a form that could easily spread between people.
Bird flu was first identified in poultry around 16 years ago and, in the rare instances when it infects people, can cause serious illness or death. It cannot currently spread between humans, but scientists wanted to find out how many genetic changes it would take for the virus to become airborne.