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H5N1 Researchers Announce End of Research Moratorium

Green light. Researchers are lifting a year-long voluntary moratorium on controversial studies involving the H5N1 avian influenza virus. Here, a scientist works in 2006 with a chicken egg containing the virus at a U.S. government laboratory designe

Centers for Disease Control and Prevention/Greg Knobloch

Almost a year after they announced it, leading influenza researchers are ending a voluntary moratorium on certain types of controversial experiments involving the H5N1 avian influenza virus.

In a letter published online today by Science and Nature, 40 researchers declare that the studies should restart now that scientists, government officials, and the public have had time to debate the need for the research and impose new safety measures. "[T]he aims of the voluntary moratorium have been met in some countries and are close to being met in others," they write, and researchers "have a public-health responsibility to resume this important work."

The move essentially ends the H5N1 controversy, which began in late 2011 when two research teams showed how to reengineer the virus, which normally infects birds, so that it could move between mammals. The discoveries touched off an intense global debate over whether journals should publish the results, which some critics feared could be used by terrorists to spark a deadly human pandemic. It also prompted discussion of whether scientists should be doing such "gain-of-function" studies at all. The results were ultimately published in Science and Nature, but the controversy prompted governments in the United States and elsewhere to impose greater oversight on H5N1 research.

Today's letter comes as little surprise to those who have been following the controversy. The moratorium, which was announced on 20 January 2012 in a letter signed by 39 leading H5N1 researchers, was originally expected to last just 60 days. But researchers extended it indefinitely in March 2012, as the debate intensified. Late last year, however, many of those who agreed to the pause began to push for lifting the moratorium as the United States and other nations finalized new schemes for reviewing H5N1 gain-of-function research proposals and implemented safety guidelines for laboratories working with especially dangerous forms of the virus. Last month, after a 2-day international meeting on the issue hosted by the U.S. National Institutes of Health, which funded the two controversial studies, key researchers and government officials said that they expected the moratorium to end soon .

H5N1 research should resume in two steps, the researchers write in today's letter. Influenza scientists working in nations that have finalized funding and lab safety rules should now be free to resume experiments that involve reengineering the virus, they write. But "[s]cientists should not restart their work in countries where, as yet, no decision has been reached on the conditions for H5N1 virus transmission research. At this time, this includes the United States and U.S.-funded research conducted in other countries." U.S.-funded researchers might not have to wait much longer to lift the moratorium, however, because officials are in the final stages of approving lab safety and proposal review guidelines.The Japanese government has also not yet finalized its rules for H5N1 research, researchers say.

"There is probably not a scientific issue in recent times that has not been so widely thrown out for public consultation as this one," one of the letter's signers, virologist Wendy Barclay of Imperial College London, said in a statement released by the Science Media Centre in London. The moratorium was needed, she said, because of a "knee jerk response from certain quarters … expressing horror that scientists were brewing up deadly diseases. It became clear that the public needed reassurance and justification about these experiments."

Now, she and other influenza researchers want to get back to trying to figure out how the H5N1 virus could become more dangerous to humans—and how health officials might be able to stop an emerging pandemic. "[B]ecause the risk exists in nature that an H5N1 virus capable of transmission in mammals may emerge," the researchers argue, "the benefits of this work outweigh the risks."

In a teleconference today, the letter's lead author said he does not expect researchers to be able to begin studies immediately. "It takes time to shut down research, and it takes time to start it back up," said virologist Ron Fouchier of Erasmus MRC in Rotterdam, the Netherlands, who led one of the controversial studies. But Fouchier already has an idea of what kinds of studies he would like to do. One focus will be figuring out exactly which mutations enable the H5N1 virus to move between mammals through the air or in respiratory droplets. Researchers have so far found "five to nine" mutations that enable transmission in mammals, he noted. Fouchier is also interested in knowing whether the same mutations can make other H5N1 strains "airborne."

*Correction, 5 p.m.: The moratorium on H5N1 research was extended indefinitely in March 2012, not March 2011.