Top Dutch scientist who re-engineered H5N1 to make it more contagious says recreating it to harm people is not easy.

A top Dutch scientist heading a team which created a mutant killer flu virus has said that publishing the results of the team’s findings will not present a serious threat to global health.

“The threat to bio-security is not as big as everybody thinks,” Ron Fouchier, whose team at the Rotterdam Erasmus Medical Centre announced the mutant version in September, told the AFP news agency on Wednesday.

“Recreating this virus is definitely not easy. You need highly-skilled people and a very large team, as well as specialised facilities, to do this type of work.”

Two top scientific journals said on Tuesday that they were mulling whether to publish full details on how Fouchier and his team mutated the H5N1 “bird flu” virus in order for it to pass from one mammal to another.

Researchers genetically altered the flu strain in a lab, making it airborne and likely to be contagious between humans for the first time.

The research has sparked fears that a pandemic causing millions of deaths could be triggered if it emerged in nature or fell into hands of bio-terrorists or rogue countries.

A US government science and advisory committee urged the US journal Science and the British journal Nature to withhold key details of Fouchier’s team’s research, so that people seeking to harm the public would not be able to manufacture the virus.

Fouchier said his team believed publishing the full findings, including a detailed description of the mutated virus, how it becomes airborne and its migration patterns, could help save lives in case of an outbreak.

“These are important details that we need to get out very quickly. This is information that needs to be shared with countries where H5N1 viruses cause outbreaks so that the countries can now be on the lookout if these mutations arise,” he said.

He said his team would respect a recommendation by the US National Science Advisory Board for Biosecurity (NSABB) that the journals withhold key details on their work, saying redrafts of their findings had been re-submitted for approval before the board.

The H5N1 strain of avian influenza is fatal in 60 percent of human cases but only 350 people have so far died from the disease, largely because it cannot, yet, be transmitted between humans.