Scientists to Pause Research on Deadly Strain of Bird Flu

The scientists who altered a deadly flu virus to make it more contagious have agreed to suspend their research for 60 days to give other international experts time to discuss the work and determine how it can proceed without putting the world at risk of a potentially catastrophic pandemic.

Suspensions of biomedical research are almost unheard of; the only other one in the United States was a moratorium from 1974 to 1976 on some types of recombinant DNA research, because of safety concerns.

A letter explaining the flu decision is being published in two scientific journals, Science and Nature, which also plan to publish reports on the research, but in a redacted form, omitting details that would let other researchers copy the experiments. The letter is signed by the scientists who produced the new, more contagious form of the flu virus, as well as by more than 30 other leading flu researchers.

“We recognize that we and the rest of the scientific community need to clearly explain the benefits of this important research and the measures taken to minimize its...