Studies of altered bird flu strains on hold

A panel of experts convened by the World Health Organization has decided to extend a moratorium on research using laboratory-modified -- and potentially dangerous -- strains of bird flu.

The 22-member panel also announced that two controversial papers on the flu, temporarily shelved by the prestigious journals Science and Nature, would not be modified and published in the near future, as originally planned. Instead, the research is likely to be published in full at a later date.

The decisions, announced Friday at the close of a two-day meeting in Geneva, follow intense months of debate over the risks and benefits of publishing the studies.

In the wild, the bird flu, designated H5N1, has proved highly lethal to humans, killing nearly 60 percent of those known to be infected. But the versions in nature do not pass easily between humans.

Ron Fouchier of the Erasmus Medical Center in the Netherlands and Dr. Yoshihiro Kawaoka of the University of Wisconsin in Madison led teams that engineered new strains of bird flu that were easily transmitted through the air between mammals. Fouchier said his strain remained highly lethal; Kawaoka reported that his strain could be managed with drugs.

Some health officials worried that if one of the new highly contagious bird flu strains somehow escaped the laboratory -- or if people with intent to do harm learned how to engineer and release lethal bird flu strains using methods published in the papers -- it could unleash a deadly global pandemic.

Many scientists, however, argued that moving ahead with the H5N1 research was essential for developing prevention strategies and treatments so they would be prepared if a pandemic were to arise naturally.

Bruce Alberts, the editor of Science, said Friday that his journal had planned to release an amended version of Fouchier's paper in mid-March. "That's not going happen" now, he said.