One H5N1 paper published while other is approved

The first of two controversial H5N1 avian influenza transmissibility studies has been published while the other has been given the go-ahead by the Dutch government and will likely be published soon.

Yoshihiro Kawaoka's study was published on Wednesday after the U.S. National Science Advisory Board for Biosecurity changed its original position to limit the publication of the two papers. Kawaoka, who works for the University of Wisconsin - Madison and the University of Tokyo, published his 11 page article on how the altered bird flu virus transmitted between ferrets by respiratory droplets in the journal Nature, Science reports.

The article explains that by introducing a mutated version of the hemagglutinin protein (H5) onto the H1N1 virus, the hybrid virus is able to bind more strongly to the cells of mammals.

The second paper, written by Ron Fouchier of Erasmus MC in Rotterdam, was held up when the Dutch government insisted that the researcher apply for an export license. He filed the application and was issued the permit on April 27. Fouchier and Kawaoka hoped that the papers would appear simultaneously.

"I regret that both papers will not appear online together, but our priority must be to serve our authors and readers," Philip Campbell, Nature's editor-in-chief, said, according to Science.

A key discovery in Kawaoka's study is the role of the virus's stalk in the ability of the flu virus to make further mutations. A mutated stalk allows the virus to make additional mutations in the more acidic environment of human mucosa. Fouchier's study is still under wraps and is currently in the editing process.

While H5N1 has not spread easily among humans, it has a high fatality rate with 355 out of 602 confirmed cases leading to death.