Scientists hard at work.... What the world really needed A new, more deadly strain of bird flu.

On December 20th American authorities said they had asked the world’s leading scientific journals to withhold research. The request, to Science and Nature, is highly unusual. But so is the research in question. Two separate teams, led by Yoshihiro Kawaoka at the University of Wisconsin, Madison, and Ron Fouchier at Erasmus Medical Centre in Rotterdam have tinkered with H5N1, otherwise known as bird flu. The resulting strains are dramatically more dangerous.

According to the World Health Organisation, bird flu has killed more than 300 people since 2003. Its toll would certainly have been far greater had it not been for H5N1's important limitation: it is not easily transmitted to humans, or between them. But if the virus ever evolved to hop nimbly from man to man, it could wreak a pandemic.

That evolution has now occurred, helped by the researchers in Madison and Rotterdam. Each team engineered the virus so that it could be transmitted through the air from ferret to ferret (good proxies for humans). Details of both studies are still under wraps but a paper Dr Fouchier presented in September at a virology conference in Malta outlines his team's approach. He and his colleagues first tried to fiddle with the flu genome directly, introducing bespoke changes to it in an effort to create an airborne strain. When this did not work, he resorted to the low-tech method of passing the virus (albeit one with three engineered mutations) from one ferret to another a number of times, giving it an opportunity to mutate naturally. After ten generations evolution worked its (in this case black) magic: the flu had gone airborne. The nasty strain had five mutations in two genes. Each of these has, Dr Fouchier notes, already been found in nature, only in separate strains and never clumped together.

The new, deadlier flu strains exist only in labs, of course. However, the fear is that if the researchers are allowed to describe the genetic changes needed to create the new strains and the precise methods used to obtain them, then terrorists or other mischief-makers can copy the techniques. H5N1 would become the atomic bomb of biological warfare.

via www.economist.com